In other words, Killian and his colleagues hope to simulate ultra-hot and ultra-dense plasmas by creating ultra-cold plasmas that are orders of magnitude less dense.
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Plasmas are often permeated by powerful forests of magnetic field lines.
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Their results are published today in a paper in Physics of Plasmas.
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These plasmas become photoionized, meaning light particles give atoms an electric charge via various processes.
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A study using this new model was published Thursday in the journal Physics of Plasmas.
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At present, telescopes measure the plasmas by recording specific wavelengths of light in the x-ray spectra.
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These results could also help scientists better understand the behavior of powerful magnetic fields and plasmas in general.
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"We are just at the beginning of exploring the implications of strong coupling in ultracold plasmas," Killian said.
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Though they're plasmas, scientists have long predicted that these squished atoms should eventually crystallize, beginning at the stars' centers.
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The room should have plenty of mahogany and leather, plasmas, darts, a grand piano and a professional full-service bar.
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These reactors often attempt to use magnetic fields to confine and heat plasmas to the point where nuclear fusion is triggered.
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Researchers in the 1970s theorized that nearby plasmas in planetary nebulae, dying stars surrounded by expelled material, might contain helium hydride.
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Then there is the issue of why the immense heat of these plasmas do not char the hands of the Jedis.
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The process that produces these bursts is called magnetic reconnection, in which different plasmas and their associated magnetic fields interact, releasing energy.
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As our general understanding of plasmas has grown, so has our ability to sustain fusion conditions for more than a hot second.
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There have been many "classic" TVs revered for their image quality through the years like the Pioneer Kuro, Panasonic plasmas, and LG OLEDs.
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The problem is that fusion plasmas do not like to be contained; these free-flowing streams of protons and electrons are tough to wrangle.
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With this limit, the hottest terrestrial objects are the quark gluon plasmas (QGPs) produced when CERN's Large Hadron Collider (LHC) collides two lead nuclei.
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But plasmas can only reach this so-called "steady state" if they can be contained, and extraordinarily hot atomic soup does not like to be contained.
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An international team of physicists has figured out a way to address this shortcoming and described their method in a new paper in Physics of Plasmas.
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He was a fellow of the American Physical Society and the American Association for the Advancement of Science, and he edited the journal Physics of Plasmas.
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Armed with the results of his study, Dr Hawker wondered if he could scale up the shrimp's technique to create plasmas that would meet the Lawson criterion.
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"I hope this will improve our models of exotic, strongly coupled astrophysical plasmas, but I am sure we will also make discoveries that we haven't dreamt of yet."
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"We're making plasmas here on Earth that are very similar to the ones out in space," says graduate student Ethan Peterson, the lead author on a paper describing the project.
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Although physicists are able to create extremely hot plasmas on Earth, replicating the extreme gravity conditions in the center of Jupiter to produce strong coupling in a lab isn't possible.
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By ignoring this energy problem, various technologies have been suggested for how a lightsaber might work, but most center on the possibility that they are plasmas with perhaps a ceramic core.
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Those first experiments, whenever they actually happen, will study the physics of deuterium-tritium plasmas in the reactor—these two isotopes of hydrogen being the front-running candidates as the fuel mixture for nuclear fusion.
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But, in a paper published recently in the Physics of Plasmas, she and her collaborator, Alex Fletcher of the Massachusetts Institute of Technology, use a type of modelling called particle-in-cell simulation to do so.
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The equation also describes drift waves in plasmas and other phenomena, and serves as "a test bed for studying turbulence and spatiotemporal chaos," said Jaideep Pathak, Ott's graduate student and the lead author of the new papers.
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In a major blow to MIT's fusion program, the feds recently pulled support for the Alcator C-Mod tokamak reactor, which produces one of the strongest magnetic fields and has yielded some of the highest pressure fusion plasmas in the world.
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Image: ETH Zurich / Julian LéonardYou learn about three or four phases of matter in school—solids, which have a shape and volume, liquids, which have a volume only, and gases and plasmas, which have neither a definite shape nor volume.
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The researchers then measured the emission spectra of the plasmas, which is similar to the measurement you do in high school chemistry where you try and identify a gas by looking at its spectral lines (except you can't see x-rays with your eyes).
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Scientists managed to confirm some of these numbers by studying the light from the residual radiation leftover from the Big Bang (also known as the cosmic microwave background), and eventually figured out how many particles of "ordinary" or baryonic matter—liquids, solids, plasmas, and gases—should be available throughout the universe.
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Cold plasma Physical and electrical Engeeniring, High pressure plasmas and Low temperature plasmas. Plasmas for Gas circuit breaker development and Plasma medicine. Transport phenomena. Dielectric materials (polymers in particular) and their integration into systems.
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Malmberg and collaborators, realized that non-neutral plasmas offer research opportunities not available with neutral plasmas. In contrast to neutral plasmas, plasmas with a single sign of charge can reach states of global thermal equilibria. The possibility of using thermal equilibrium statistical mechanics to describe the plasma provides a large advantage to theory.
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Laroussi's research interests are in the Physical Electronics area, particularly in the applications of non-equilibrium gaseous discharges. Amongst these are the generation of large volume low temperature plasmas, the interaction of microwaves with plasmas, and the biomedical applications of cold plasmas, a field known as “Plasma Medicine”. In the latter, he published seminal papers on the interaction of low temperature plasmas with biological cells. In plasma medicine research, low temperature plasmas (or simply cold plasmas) are used to inactivate bacteria and proteins, assist in wound care, destroy some types of cancer cells, and play an active role in various other medical therapies.
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The parameters of plasmas, including their spatial and temporal extent, vary by many orders of magnitude. Nevertheless, there are significant similarities in the behaviors of apparently disparate plasmas. Understanding the scaling of plasma behavior is of more than theoretical value. It allows the results of laboratory experiments to be applied to larger natural or artificial plasmas of interest.
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A plasma is any gas in which a significant percentage of the atoms or molecules are ionized. Fractional ionization in plasmas used for deposition and related materials processing varies from about 10−4 in typical capacitive discharges to as high as 5–10% in high density inductive plasmas. Processing plasmas are typically operated at pressures of a few millitorr to a few torr, although arc discharges and inductive plasmas can be ignited at atmospheric pressure. Plasmas with low fractional ionization are of great interest for materials processing because electrons are so light, compared to atoms and molecules, that energy exchange between the electrons and neutral gas is very inefficient.
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Neutral plasmas are notoriously difficult to confine. In contrast, Malmberg and collaborators predicted and demonstrated experimentally that plasmas with a single sign of charge, such as pure electron or pure ion plasmas, can be confined for long periods (e.g., hours). This was accomplished using an arrangement of electric and magnetic fields similar to that of a Penning trap, but optimized to confine single-component plasmas. In recognition of Malmberg’s contributions to the development of these devices, they are now referred to as Penning–Malmberg traps.
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Many types of plasmas can be used for surface activation. However, due to economic reasons, atmospheric pressure plasmas found most applications. They include arc discharge, corona discharge, dielectric barrier discharge and its variation piezoelectric direct discharge.
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Alfven wave current drive experiments in spherical tokamak plasmas Alfven wave can generate toroidal plasma current without density limits. This is very favourable for spherical tokamak plasmas, which have very high dielectric constants that makes LHCD or ECCD very hard.
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Astrophysical plasma may also be studied in a variety of ways as they emit electromagnetic radiation across a wide range of the electromagnetic spectrum. Because astrophysical plasmas are generally hot, electrons in the plasmas are continually emitting X-rays through the process called bremsstrahlung. This radiation may be detected with X-ray telescopes located in the upper atmosphere or in space. Astrophysical plasmas also emit radio waves and gamma rays.
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Devices have been proposed where the negative cage is magnetically insulated from the incoming plasmas.
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Plasmas in stars can both generate and interact with magnetic fields, resulting in a variety of dynamic astrophysical phenomena. These phenomena are sometimes observed in spectra due to the Zeeman effect. Other forms of astrophysical plasmas can be influenced by preexisting weak magnetic fields, whose interactions may only be determined directly by polarimetry or other indirect methods. In particular, the intergalactic medium, the interstellar medium, the interplanetary medium and solar winds consist of diffuse plasmas.
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A dusty plasma contains tiny charged particles of dust (typically found in space). The dust particles acquire high charges and interact with each other. A plasma that contains larger particles is called grain plasma. Under laboratory conditions, dusty plasmas are also called complex plasmas.
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SPIE vol. 9635, 96350X (2015). Hydrogen plasmas can also etch silicon as well.C. Ghica et al.
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Vargas-Blanco received his doctorate in Plasmas and Nuclear Fusion from the Complutense University of Madrid, Spain in 2008. His PhD thesis entitled "Transporte local en plasmas ECRH de un dispositivo Heliac de confinamiento magnético" (Local transport in ECRH plasmas of a Heliac magnetic confinement device)Tesis Doctoral Iván Vargas Blanco, 2008. Laboratorio Nacional de Fusión – Ciemat. is carried out at the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT) where the National Fusion Laboratory is located.
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They saponify insoluble viscosities and dislocate the hard congregations enabling them to be pulled by circulating plasmas.
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The CNT group installed a conducting boundary in August 2007 to study its effects on confinement times, and to allow measurements in the absence of internal rods. Future plans for CNT include the study of electron-positron plasmas confined on magnetic surfaces and further studies of partly neutralized plasmas.
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John Holmes Malmberg (July 5, 1927 – November 1, 1992) was an American plasma physicist and a professor at the University of California, San Diego. He was known for making the first experimental measurements of Landau damping of plasma waves in 1964, as well as for his research on non-neutral plasmas and the development of the Penning–Malmberg trap. In 1985, Malmberg won the James Clerk Maxwell Prize for Plasma Physics for his experimental work on wave- particle interactions in neutral plasmas and his studies on pure electron plasmas. He was later co-awarded the John Dawson Award for Excellence in Plasma Physics Research in 1991 for his contribution to research on non- neutral plasmas.
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PK-3 Plus studies complex plasmas - plasmas that contain microparticles. The microparticles acquire high negative charges by collecting electrons from the surrounding plasma. They interact with each other and with the plasma particles, e.g., they experience a drag force from the ions that are streaming to the edges of the plasma.
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To inject the target plasmoid into the fusion compression chamber two plasmoids are accelerated at high velocity with pulsed magnetic fields and merge into a single target plasmoid at high pressure. Their 2018 experiments achieved plasmas with multi-keV temperatures. Published records show plans to compress fusion plasmas to 12 Tesla.
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Early papers describe the plasma-propellant interaction group at ARL and their attempts to understand and distinguish between the chemical, thermal, and radiation effect of plasmas on conventional solid propellants. Using scanning electron microscopy and other diagnostic techniques, they evaluated in detail the influence of plasmas on specific propellant materials.
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The coupling constant of a plasma is given by the ratio of its average Coulomb-interaction energy to its average kinetic energy—or how strongly the electric force of each atom holds the plasma together . Plasmas can therefore be categorized into weakly- and strongly-coupled plasmas depending upon the value of this ratio. Many of the typical classical plasmas, such as the plasma in the solar corona, are weakly coupled, while the plasma in a white dwarf star is an example of a strongly coupled plasma.
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In 1985, Malmberg received the James Clerk Maxwell Prize for Plasma Physics from the American Physical Society for "his outstanding experimental studies which expanded out understanding of wave-particle interactions in neutral plasmas and increased our confidence in plasma theory; and for his pioneering studies of the confinement and transport of pure electron plasmas". And in 1991, he was co-awarded the John Dawson Award for Excellence in Plasma Physics Research with Charles F. Driscoll and Thomas Michael O'Neil, for their studies of single-component electron plasmas.
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The Chromo–Weibel instability is a plasma instability present in homogeneous or nearly homogeneous non-abelian plasmas which possess an anisotropy in momentum space. In the linear limit it is similar to the Weibel instability in electromagnetic plasmas but due to non-linear interactions present in non- abelian plasmas the late development of this instability is characterized by a turbulent cascade of modes. This instability is relevant in the understanding of the early-time dynamics of the quark-gluon plasma as produced in heavy-ion collisions.
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The runaway electron phenomenon has been observed in high energy plasmas. They can pose a threat to machines and experiments in which these plasmas exist, including ITER. Several studies exist examining the properties of runaway electrons in these environments (tokamak), searching to better suppress the detrimental effects of these unwanted runaway electrons.
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The START team would test the MHD using forty-six sets of Mirnov coils at different heights on the center column of START. Plasmas being formed by compression within START limited the fluctuation of the MHD.Hender, T. C., et al. "Magneto-Hydro-Dynamic Limits In Spherical Tokamaks." Physics Of Plasmas 6.5 (1999): 1958.
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Physics Reports, Vol. 540, 123166., can be used for wound treatmentLaroussi, M.(2009) Low Temperature Plasmas for Medicine. IEEE Trans.
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Plasmas as high as 3 kiloelectronvolts in temperature and about 8/cc in density are routinely formed for various experiments.
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As its predecessors, PK-4 Plus studies complex plasmas, which are low temperature plasmas that contain highly charged microparticles. The microparticles interact with each other and with the plasma and can be used to study a variety of topics, for instance waves , the influence of microparticles on the plasma, string formation, and shear flow.
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Godyak is a fellow of the American Physical Society and the IEEE. In 2004, he received the James Clerk Maxwell Prize for Plasma Physics with Noah Hershkowitz for "fundamental contributions to the physics of low temperature plasmas, including radio frequency wave heating, sheath physics, potential profiles, diagnostic probes, and the industrial applications of plasmas".
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Relativistic plasmas in physics are plasmas for which relativistic corrections to a particle's mass and velocity are important. Such corrections typically become important when a significant number of electrons reach speeds greater than 0.86c (Lorentz factor \gamma=2). Such plasmas may be created either by heating a gas to very high temperatures or by the impact of a high-energy particle beam. A relativistic plasma with a thermal distribution function has temperatures greater than around 260 keV, or 3.0 GK (5.5 billion degrees Fahrenheit), where approximately 10% of the electrons have \gamma > 2.
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The similarity theory allows deriving non-trivial power-law scalings for the energy of fast electrons in underdense and overdense plasmas.
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One generally uses the term bremsstrahlung losses in the context when the plasma cooling is undesired, as e.g. in fusion plasmas.
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Surko is a fellow of the American Physical Society and the American Association for the Advancement of Science. In 2014, he received the James Clerk Maxwell Prize for Plasma Physics for "the invention of and development of techniques to accumulate, confine, and utilize positron plasmas, and for seminal experimental studies of waves and turbulence in tokamak plasmas".
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Biology and health (as for instance plasmas for cancer therapy, gene transfection, decontamination and sterilisation) Environment and energy. Transport. Aeronautics and space.
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The term nonthermal plasma includes anisothermal plasmas and means that the different degrees of freedom of the plasma are not in thermal equilibrium.
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His work was in the alternative use of laser, electron and ion beams to heat thermonuclear plasmas for use as alternative energy sources.
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In 2001, he became director of the Center for Theoretical Physics and in 2009, the director of the Institute for Lasers and Plasmas.
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The PK-4 or (Plasmakristall-4) laboratory is a joint Russian-European laboratory for the investigation of dusty/complex plasmas on board the International Space Station (ISS), with the principal investigators at the Institute of Materials Science at the German Aerospace Center (DLR) and the Russian Institute for High Energy Densities of the Russian Academy of Sciences. It is the third laboratory on board the ISS to study complex plasmas, after the PKE Nefedov and PK-3 Plus experiments. In contrast to the previous setups, the geometry was significantly changed and is more suited to study flowing complex plasmas.
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The gas used for plasma nitriding is usually pure nitrogen, since no spontaneous decomposition is needed (as is the case of gas nitriding with ammonia). There are hot plasmas typified by plasma jets used for metal cutting, welding, cladding or spraying. There are also cold plasmas, usually generated inside vacuum chambers, at low pressure regimes. Usually steels are beneficially treated with plasma nitriding.
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Surface-wave-sustained plasmas (SWP) can be operated in a large variety of recipient geometries. The pressure range accessible for surface-wave-excited plasmas depends on the process gas and the diameter of the recipient. The larger the chamber diameter, the lower the minimal pressure necessary for the SWP mode. Analogously, the maximal pressure where a stable SWP can be operated decreases with increasing diameter.
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The University of Sydney in Australia conducts polywell experiments. They published five papers in Physics of Plasmas on this topic."The dependence of potential well formation on the magnetic field strength and electron injection current in a polywell device" S. Cornish, D. Gummersall, M. Carr and J. Khachan Phys. Plasmas 21, 092502 (2014) They also published two PhD theses and presented their work at IEC Fusion conferences.
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Noah Hershkowitz (born August 16, 1941) is an American experimental plasma physicist. He was jointly awarded the 2004 James Clerk Maxwell Prize for Plasma Physics with Valery Godyak for his research on low-temperature plasmas. These include radio frequency wave heating, sheath physics, potential profiles, diagnostic probes, and the industrial applications of plasmas. He is also known to have worked on magnetic confinement fusion (i.e.
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He has coauthored the textbook, Introduction to Dusty Plasma Physics, and edited or co-edited 15 books and several (18) Special Issues of various journals. He is the discoverer of the dust acoustic wave in dusty plasmas and novel attractive force between ions at atomic dimensions in quantum plasmas. He has more than 30 years of experience in committee work both at national and international levels.
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Theodor V. Ionescu (February 8, 1899 - November 7, 1988) was a Romanian physicist and inventor who made remarkable discoveries in plasma physics, ionosphere physics, ion coupling electrons in dense plasmas, masers, magnetron amplifiers, and Zeeman effects related to controlled nuclear fusion and quantum emission mechanisms in hot plasmas. He was a member of the Romanian Academy since December 21, 1935.Elvira Botez. Academia de Științe din România.
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An Anisothermal plasma is a plasma which thermal state can be approximated by more than one temperature for the different degrees of freedom of the plasma. The degrees of freedom refer to translation (kinetic energy), rotation, vibration of each particle type. Examples of anisothermal plasmas can be found among low-pressure plasmas that are excited by high frequency electric fields, see frequency classification of plasmas. They generally exhibit hot electrons that are powered by the alternating electric field, and a neutral and ion component, which is significantly colder due to the low efficiency of the energy transfer between light electrons and heavy neutrals and ions.
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The Volterra lattice is an integrable system, and is related to the Toda lattice. It is also used as a model for Langmuir waves in plasmas.
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Mounir Laroussi Mounir Laroussi, is a Tunisian-American scientist. He is known for his work in plasma science, especially low temperature plasmas and their biomedical applications.
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Gates, D.A., and R. Akers. "High-Performance Discharges In The Small Tight Aspect Ratio Tokamak (START)." Physics Of Plasmas 5.5 (1998): 1775. Academic Search Premier. Web.
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They have been observed as electron phase space holes (electrostatic solitary structures) and double layers in space plasmas, as well as in scattering experiments in the laboratory.
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Its existence in cosmic plasmas has not been confirmed. In 1986, Gerhard Haerendel, suggested that critical velocity ionization may stabilize the plasma flow in a cometary coma,.
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The flux freezing indicates that the magnetic field topology cannot change in a perfectly conducting fluid. However, this would lead to highly tangled magnetic fields with very complicated topologies that should impede the fluid motions. Nevertheless, astrophysical plasmas with high electrical conductivities do not generally show such complicated tangled fields. Also magnetic reconnection seems to occur in these plasmas unlike what is expected from the flux freezing conditions.
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Fusion plasmas are typically generated from ionization of a neutral gas. In most cases, an isotope of hydrogen — called deuterium — is used as the plasma fuel. These plasmas are therefore primarily made up of deuterium ions (plus electrons), and it is necessary to diagnose the behavior of these ions if the relevant plasma physics is to be understood. However, in any fusion device, other types of ions ("impurities") are also present.
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Becker focuses on the experimental and theoretical study of electron-driven processes in plasmas. Becker was part of a group of scientists leading the research on the determination of ionization cross sections of atoms and molecules. Their research worked toward the understanding of the charge carrier formation in plasmas. Becker also researches the properties of basic atmospheric-pressure microplasmas and their use in environmental, biological, and biomedical applications.
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The first use of the RW technique for antimatter was done using small positron plasmas without coupling to modes. The strong drive regime, which was discovered somewhat later using electron plasmas, has proven to be more useful in that tuning to (and tracking) plasma modes is unnecessary. A related technique has been developed to compress single-component charged gases in PM traps (i.e., charge clouds not in the plasma regime).
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Energy transport and the propagation of waves plays an important role in the wave heating of plasmas. Power-flow trajectories of electromagnetic waves through a spatially nonuniform plasma can be computed using direct solutions of Maxwell's equations. Another way of computing the propagation of waves in the plasma medium is by using Ray tracing method. Studies of wave propagation in plasmas using ray tracing method can be found in.
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Gregor Eugen Morfill (born 23 July 1945 in Oberhausen, Germany) is a German physicist who works in basic astrophysical research and deals with complex plasmas and plasma medicine.
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Due to his interest to establish new generations of scientists in the field of plasmas and fusion, Vargas-Blanco has taught the course "Plasma Physics and Applications I" for more than eight years at the Tecnológico de Costa Rica. This is a course that covers the introduction to the plasmas physics, charged particles in magnetic and electric fields, plasma as fluids, waves in plasmas, collisions, conductivity and diffusion, and the discharges types. By 2018, around 200 university students have enrolled into this course. In 2018, he taught the second course "Plasma Physics for Engineering II", adding topics as: plasma generation, introduction to plasma diagnosis, computational plasma physics, and plasma for nuclear fusion and surface treatment by plasma.
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He then played a major part in developing the "ballooning transformation" for toroidal plasmas, along with Jack Connor and Jim Hastie, which won him the 2004 Hannes Alfvén Prize.
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Philippa K. Browning is a Professor of Astrophysics in the Jodrell Bank Centre for Astrophysics at the University of Manchester. She specialises in the mathematical modelling of fusion plasmas.
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Techniques have been developed to measure the plasma length, radius, temperature, and density in the trap, and to excite plasma waves and oscillations. It is frequently useful to compress plasmas radially to increase the plasma density and/or to combat asymmetry-induced transport. This can be accomplished by applying a torque on the plasma using rotating electric fields [the so-called “rotating wall” (RW) technique], or in the case of ion plasmas, using laser light.
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He received the Leadership Award from Fusion Power Associates in 1986 and the 2005 IEEE Particle Accelerator Science and Technology Award. In 2008, Davidson received the James Clerk Maxwell Prize for Plasma Physics for "pioneering contributions to the physics of one-component non-neutral plasmas, intense charge particle beams, and collective nonlinear interaction processes in high-temperature plasmas." A resident of Cranbury, New Jersey, Davidson died on May 19, 2016, at his home.Chang, Kenneth.
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130: 102-102. Unfortunately, the system was unable to meet any of these goals. The reasons for these problems were intensively studied over the following years, leading to a new understanding of the instabilities of high- performance plasmas that had not been seen in smaller machines. A major outcome of TFTR's troubles was the development of highly non-uniform plasma cross-sections, notably the D-shaped plasmas that now dominate the field.
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Kenneth Ivan Golden from the University of Vermont, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Division of Plasma Physics in 1991, for pioneering work in the theory of dynamical processes in strongly coupled plasmas; for extending the theory to the analysis of binary ion mixtures and of two dimensional electron systems; for contributions to the theory of the structure of shock waves in magnetized plasmas.
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Kenneth W. Gentle from the University of Texas, Austin, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Division of Plasma Physics in 1996, for his pioneering experiments on wave- particle and wave-wave interactions which have illuminated the fundamental nonlinear phenomena in collisionless plasmas, and for his leadership in the development of experiments which directly measure the fundamental processes of transport in Tokamak plasmas.
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2016 James Clerk Maxwell Prize for Plasma Physicist Recipient, Ellen G. Zweibel, citation, APS website She investigates astrophysical phenomena and plasmas physics of the sun, stars, galaxies, and clusters of galaxies.
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Tore Supra operated between 1988 and 2010. Its goal was to create long-duration plasmas. The upgrade to WEST took place between 2013 and 2016. WEST has been operating since 2016.
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Frances "Fran" Bagenal (born 1954) is a Professor of Astrophysical and Planetary Sciences at the University of Colorado Boulder and a researcher in the fields of space plasmas and planetary magnetospheres.
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Burrell is a fellow of the American Physical Society (1985) and the Institute of Physics. In 2001, Burrell received the Excellence in Plasma Physics Award (now known as the John Dawson Award for Excellence in Plasma Physics Research) from the American Physical Society for "experiments that show that sheared ExB flows can suppress turbulence and transport in tokamak plasmas and that such flows can spontaneously arise at the edge and in the core of tokamak plasmas.". In 2018, he received the James Clerk Maxwell Prize for Plasma Physics for "pioneering research, including key experimental advances and diagnostic development, that established the links between sheared plasma flow and turbulent transport, leading to improved confinement regimes for magnetized plasmas through turbulent transport reduction by sheared flow".
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In the resonator mode, the plasma density does not exceed the critical density. A standing electromagnetic wave, which is confined by a resonator cavity, penetrates the plasma and sustains it in the regions of highest field intensity. The geometry of this region determines the spatial distribution of the plasma. Plasmas excited in resonator mode are less resistant against detuning, for instance by the insertion of electric probes (Langmuir probes) or electrically conducting samples compared to surface-wave plasmas.
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In 1966, he became a professor at Yale University. He was Professor of Astrophysical Sciences in 1967 until he retired in 2004. In 1993, he received the James Clerk Maxwell Prize in Plasma Physics for "his pioneering contributions to basic plasma theory, to the physics of magnetically confined plasmas, and to plasma astrophysics. His important work en-compasses plasma equilibria and stability, adiabatic invariance, ballooning modes, runaway electrons, colliding beams, spin-polarized plasmas, and cosmic-ray instabilities".
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In early 2010s, Iacopi worked on the demonstration that cold plasmas can be an effective solution to slow down the diffusion of reactive species into porous media. She wrote an article in 2011 about the cryogenic plasmas and nanoporous materials. Through her research, Iacopi demonstrated that by processing plasma at cryogenic temperatures, the diffusion of plasma into nanoporous materials can be considerably suppressed. She further demonstrates that this suppression is controlled by reaction factors, radical recombination and sticking coefficient.
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Patrick Mora (born 1952) is a French theoretical plasma physicist who specializes in laser-plasma interactions. He was awarded the 2014 Hannes Alfvén Prize and 2019 Edward Teller Award for his contributions to the field of laser-plasma physics. Mora is a research director of the French National Centre for Scientific Research (CNRS) and a professor at the École Polytechnique in Paris, where he is also director of the Institut Lasers et Plasmas (Institute for Lasers and Plasmas).
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Fusion plasmas using D-T fuel produce 3.5 MeV alpha particles and 14.1 MeV neutrons. By measuring the neutron flux, plasma properties such as ion temperature and fusion power can be determined.
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The internal gas core temperatures in most designs vary, but the designs with the highest specific impulses generally have fissioning gas plasmas heating a low mass propellant. This heating occurs primarily through radiation.
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Tetsuji Oda from the University of Tokyo, Japan was named Fellow of the Institute of Electrical and Electronics Engineers (IEEE) in 2015 for contributions to electrostatics and high-pressure plasmas for environmental protection.
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Physics of Plasmas is a peer-reviewed monthly scientific journal on plasma physics published by the American Institute of Physics, with cooperation by the American Physical Society's Division of Plasma Physics, since 1994. Until 1988, the journal topic was covered by Physics of Fluids. From 1989 until 1993, Physics of Fluids was split into Physics of Fluids A covering fluid dynamics and Physics of Fluids B dedicated to plasma physics. In 1994, Physics of Plasmas was split off as a separate journal.
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In 2009 the Institute of Electric and Electronics Engineers (IEEE) elevated Laroussi to Fellow for his contributions to the biomedical applications of plasmas[3]. Laroussi's best known invention is the Plasma Pencil. This device can generate long plumes or jets of cold plasmas that can be used in various biomedical applications, including in dentistry. The Plasma Pencil was the subject of wide media coverage including a mention in an article in National Geographic (February 2006 issue), and ABC online news.
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Clifford Michael Surko (born October 11, 1941 in Sacramento, California) is an American physicist, whose works involve plasma physics, atomic physics, nonlinear dynamics and solid state physics. Together with his colleagues, he developed techniques for laser scattering at small angles to study waves and turbulence in tokamak plasmas and invented a positron trap (buffer gas positron trap) that was used in experiments worldwide to study antimatter. Surko also developed other techniques for studying positron plasmas and examined atomic and plasma physics with positrons.
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In 1996, he received the James Clerk Maxwell Prize for Plasma Physics for "seminal contributions to plasma theory, including extension of Landau damping to the nonlinear regime and demonstration of the importance of particle trapping; discovery of the plasma-wave echo; and pioneering studies of the confinement, transport, and thermal equilibria of non-neutral plasmas, liquids and crystals. His theoretical work and active guidance of experiments with trapped, non-neutral plasmas provide much of the foundation for this branch of plasma physics".
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It presents the results of thermal transport characterization in plasmas of the Spanish Stellarator TJ-II and its dependence on density, rotational transformation and heating power. Additionally, it shows results of the study of particle transport in this device and its dependence on density.Density dependence of particle transport in ECH plasmas of the TJ-II stellarator. Vargas-Blanco's work represents one of the first scientific evidences of the influence and improvement of thermal confinement due to the rational surfaces in Stellarator devices.
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The strength and range of the electric force and the good conductivity of plasmas usually ensure that the densities of positive and negative charges in any sizeable region are equal ("quasineutrality"). A plasma with a significant excess of charge density, or, in the extreme case, is composed of a single species, is called a non-neutral plasma. In such a plasma, electric fields play a dominant role. Examples are charged particle beams, an electron cloud in a Penning trap and positron plasmas.
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IPFN is organized in seven research groups: Engineering and Systems Integration, Experimental Physics, Materials Processing and Characterisation, Theory and Modelling, Lasers and Plasmas, Gas Discharges and Gaseous Electronics, and High Pressure Plasmas. The activities in the frame of the Associate Laboratory are evaluated by an External Evaluation Committee. IPFN is also the research unit of the Contract of Association between EURATOM and IST, in force since 1990. These activities are coordinated by the Head of Research Unit and monitored by a steering committee.
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On 18 March 2015, he was elected the 31st President of Corpus Christi College, Oxford, his alma mater: he took up the post on 1 October 2016. He is the first scientist to hold the post. On 1 July 2018, he was appointed director of the Princeton Plasma Physics Laboratory (PPPL). Cowley's research interests are in plasmas and nuclear fusion, in astrophysical plasmas and the laboratory, such as the Joint European Torus (JET) and the International Thermonuclear Experimental Reactor (ITER).
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First plasma was obtained on NSTX on Friday, February 12, 1999 at 6:06 p.m. Magnetic fusion experiments use plasmas composed of one or more hydrogen isotopes. For example, in 1994, PPPL's Tokamak Fusion Test Reactor (TFTR) produced a world-record 10.7 megawatts of fusion power from a plasma composed of equal parts of deuterium and tritium, a fuel mix likely to be used in commercial fusion power reactors. NSTX was a "proof of principle" experiment and therefore employed deuterium plasmas only.
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But Evgeny Velikhov first discovered theoretically in 1962 and experimentally in 1963 that an ionization instability, later called the Velikhov instability or electrothermal instability, quickly arises in any MHD converter using magnetized nonthermal plasmas with hot electrons, when a critical Hall parameter is reached, hence depending on the degree of ionization and the magnetic field. Such an instability greatly degrades the performance of nonequilibrium MHD generators. The prospects about this technology, which initially predicted awesome efficiencies, crippled MHD programs all over the world as no solution to mitigate the instability was found at that time. Consequently, without implementing solutions to master the electrothermal instability, practical MHD generators had to limit the Hall parameter or use moderately heated thermal plasmas instead of cold plasmas with hot electrons, which severely lowers efficiency.
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"Dried plasmas" in powder or strips of material format were developed and first used in World War II. Prior to the United States' involvement in the war, liquid plasma and whole blood were used.
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Mora developed a theory of the expansion of plasmas into vacuum, which explains the flow dynamics and structure of the ion front. His theories are used to explain ion and electron beam acceleration experiments.
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''' The resistive ballooning mode (RBM) is an instability occurring in magnetized plasmas, particularly in magnetic confinement devices such as tokamaks, when the pressure gradient is opposite to the effective gravity created by a magnetic field.
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As of late 2011, several research facilities have demonstrated active control or suppression of ELMs in tokamak plasmas. For example, the KSTAR tokamak uses specific asymmetric three-dimensional magnetic field configurations to achieve this goal.
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In 1967, Griem was elected a fellow of the American Physical Society. In 1991, he received the James Clerk Maxwell Prize for Plasma Physics for "his numerous contributions to experimental plasma physics and spectroscopy, particularly in the area of improved diagnostic methods for high temperature plasmas, and for his books on plasma spectroscopy and spectral line broadening in plasmas that have become standard references in the field". Griem also received a Guggenheim Fellowship, a Humboldt Award and the William F. Meggers Award of the Optical Society.
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Boris Borisovich Kadomtsev (; 9 November 1928 – 19 August 1998) was a Russian plasma physicist who worked on controlled fusion problems (e.g. tokamaks). He developed a theory of transport phenomena in turbulent plasmas and a theory of the so-called anomalous behavior of plasmas in magnetic fields. In 1966, he discovered plasma instability with trapped particles. In 1970, Kadomtsev and Vladimir Petviashvili introduced into plasma physics the Kadomtsev–Petviashvili equation (KP equation), a nonlinear partial differential equation with applications in theoretical physics and complex analysis.
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Capacitive plasmas are usually very lightly ionized, resulting in limited dissociation of precursors and low deposition rates. Much denser plasmas can be created using inductive discharges, in which an inductive coil excited with a high-frequency signal induces an electric field within the discharge, accelerating electrons in the plasma itself rather than just at the sheath edge. Electron cyclotron resonance reactors and helicon wave antennas have also been used to create high-density discharges. Excitation powers of 10 kW or more are often used in modern reactors.
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Patrick Henry Diamond is an American theoretical plasma physicist. He is currently a professor at the University of California, San Diego, and a director of the Fusion Theory Institute at the National Fusion Research Institute in Daejeon, South Korea, where the KSTAR Tokamak is operated. In 2011, Diamond was jointly awarded the Hannes Alfvén Prize with Akira Hasegawa and Kunioki Mima for important contributions to the theory of turbulent transport in plasmas. In addition to applications in controlled nuclear fusion, he also specializes in astrophysical plasmas.
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At Auburn, Thomas studies multiple aspects of plasma physics, including wave-particle interactions in plasma-phase materials and the effects of microgravity upon dusty plasmas. He is an associate editor of the Journal of Plasma Physics.
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Since these temperatures are so high, most relativistic plasmas are small and brief, and are often the result of a relativistic beam impacting some target. (More mundanely, "relativistic plasma" might denote a normal, cold plasma moving at a significant fraction of the speed of light relative to the observer.) Relativistic plasmas may result when two particle beams collide at speeds comparable to the speed of light, and in the cores of supernovae. Plasmas hot enough for particles other than electrons to be relativistic are even more rare, since other particles are more massive and thus require more energy to accelerate to a significant fraction of the speed of light. (About 10% of protons would have \gamma > 2 at a temperature of 481 MeV - 5.6 TK.) Still higher energies are necessary to achieve a quark–gluon plasma.
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Morfill is the author and co-author of over 500 scientific publications and a popular science book on chaos theory. In addition to his astrophysical work, Gregor Morfill makes important contributions to the subject of "dusty complex plasmas" (with application to space plasmas and the explanation of the structure of Saturn rings), to the discovery of plasma crystals as a solid state of aggregation of dusty plasmas (discovered in 1994) and to microscopic analysis of the melting process in plasma crystals. He also participates in space plasma experiments with the International Space Station (ISS), such as the experiment PKE-Nefedov (2001-2005) in cooperation with the Russian space agency and the Institute for High Energy Densities (IHED, JIHT) in Moscow. Morfill also researches applications of plasma in medicine such as in the treatment of chronic wounds.
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He was awarded in honor of his work in high-temperature plasma physics and fusion research, especially for the discovery of self-organizing transport barriers (i.e. H-mode), which was groundbreaking for the mastery of fusion plasmas.
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All welding arcs are (partially ionized) plasmas, but the one in plasma arc welding is a constricted arc plasma. Just as oxy-fuel torches can be used for either welding or cutting, so too can plasma torches.
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It has also been shown to be more effective than sodium fluoride in controlling gingivitis. Tin is also used as a target to create laser induced plasmas which act as the light source for Extreme ultraviolet lithography.
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Electrons, molecules (atoms), excited species and ions form a soup of species which involves many interactions between species and demonstrate collective behavior under the influence of external electric and magnetic fields. Light always accompanies plasmas: as the excited species relax and move to lower energy levels, energy is released in the form of light. Microplasma is a subdivision of plasma in which the dimensions of the plasma can range between tens, hundreds, or even thousands of micrometers in size. The majority of microplasmas that are employed in commercial applications are cold plasmas.
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Whilst at Princeton, Porkolab concentrated on dispersive properties of plasma waves and instabilities in magnetized plasmas. Measurements corroborating the validity of the collisionless Boltzmann equation and demonstrating nonlinear scattering of Bernstein waves with wavelengths comparable to the electron Larmor radius were obtained. Porkolab's work provided experimental verifications of Landau damping, nonlinear resonant wave-wave scattering and parametric instabilities, also predicting upper hybrid solitons. From 1977, whilst at the MIT Physics Department, Porkolab joined the newly established MIT Plasma Science and Fusion Center, where he began experiments on lower hybrid current drive in tokamak plasmas.
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The BGT was invented in the 1980s, originally intended to study positron transport in tokamak (fusion) plasmas. Subsequently, the technique was refined and is now used in laboratories worldwide for a variety of applications. They include study of positron interactions with atoms and molecules, materials, and material surfaces; the creation of antihydrogen, the positronium molecule (i.e., Ps2, e+e−e+e−), and novel positron and positronium beams. BGTs are also expected to play similarly important roles in efforts to create and study positoronium atom Bose–Einstein condensates (BEC) and a classical electron-positron “pair” plasmas.
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In addition to the obvious intellectual benefits brought by increased understanding of our space environment, there are many practical motivations for enhancing our knowledge of space plasmas. The heliosphere is a protective cocoon for the Solar System, just as the Earth's magnetosphere is a protective cocoon for the Earth. The insight provided by ENAs into the behaviour of space plasmas improves our understanding of these protective mechanisms. Without the magnetosphere, Earth would be subject to direct bombardment by the solar wind and may be unable to retain an atmosphere.
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Karissa's early research was in plasma physics. She earned her PhD in astrophysical sciences at University of Colorado Boulder under Martin V. Goldman (a student of Donald F. Dubois). Her dissertation entailed analytical treatments of non-linear wave-wave interactions in plasmas, elucidating the competition between Langmuir wave-wave and wave-particle effects in the auroral ionosphere. In 1997, after earning her doctorate, Sanbonmatsu joined Los Alamos National Laboratory as a postdoctoral scholar under Donald F. Dubois (a student of Murray Gell-Mann), determining the effect of kinetic processes on Langmuir waves in plasmas.
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3) "Atoms, Solids and Plasmas in Super-Intense Laser Fields" (with D. Batani, S. Martellucci and A.N. Chester), Kluwer Academic-Plenum, New-York (2001). 4) "Atoms and Plasmas in Super-Intense Laser Fields" (with D. Batani and S. Martellucci), Conference Proceedings, Volume 88, Italian Physical Society, Bologna (2004). He is also the author of hundred and forty- seven research articles and forty-five review articles in theoretical physics, devoted mainly to quantum collision theory with applications to atomic, nuclear and high-energy processes and to the theory of high-intensity laser- atom interactions.
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Chen graduated from the Affiliated Senior High School of National Taiwan Normal University in 1962. In 1966, he took his undergraduate degree at National Taiwan University. Chen went to United States for graduate schooling in 1967, where he obtained a Master of Science Degree from Washington State University, Pullman in 1969, and a Doctor of Philosophy Degree from the University of California, Berkeley under the supervision of Charles K. Birdsall in 1972, for his research work I. Heating of Magnetized Plasmas by Large-Amplitude Electric Field. II. Reduction of the Grid Effects in Simulation Plasmas.
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Scientists are interested in active galactic nuclei because such astrophysical plasmas could be directly related to the plasmas studied in laboratories. Many of these phenomena seemingly exhibit an array of complex magnetohydrodynamic behaviors, such as turbulence and instabilities. Although these phenomena may occur on astronomical scales as large as the galactic core, many astrophysicists suggest that they do not significantly involve plasma effects but are caused by matter consumed by super massive black holes. In Big Bang cosmology, the entire universe was in a plasma state prior to recombination.
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Quantemol Ltd is based in University College London initiated by Professor Jonathan Tennyson FRS and Dr. Daniel Brown in 2004. The company initially developed a unique software tool, Quantemol-N, which provides full accessibility to the highly sophisticated UK molecular R-matrix codes, used to model electron polyatomic molecule interactions. Since then Quantemol has widened to further types of simulation, with plasmas and industrial plasma tools, in Quantemol-VT in 2013 and launched in 2016 a sustainable database Quantemol-DB, representing the chemical and radiative transport properties of a wide range of plasmas.
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Mora developed a widely used model of the interaction of laser light with plasmas in connection with energy transport in plasma and plasma hydrodynamics. With his colleague Jean-Francois Luciani, he also developed a nonlinear and non-local theory of heat transport in a plasma via electrons. This has applications in improving numerical simulations in laser- driven inertial fusion. With Tom Antonsen, he developed a model of the propagation of laser pulses in non-dense plasmas that revealed their tendency to self-focus or to display Raman scattering.
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The Center for Integrated Plasma Studies (CIPS) is a research center at the University of Colorado Boulder. This center was founded in 1993, in order to consolidate and facilitate plasma physics research on the University of Colorado Boulder campus. Today CIPS is involved with research in plasma physics, space plasmas, dusty plasmas, plasma diagnostics, and nuclear fusion. CIPS is located in the Duane Physics building on the University of Colorado Boulder Campus, and has about 20 research faculty and about 20 graduate and undergraduate students and support staff.
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Nevertheless, it can result in non-negligible macroscopic effects, particularly in conducting media such as metals, electrolytes and plasmas. Spatial dispersion also plays role in optical activity and Doppler broadening, as well as in the theory of metamaterials.
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Magnetohydrodynamics is the multi- disciplinary study of the flow of electrically conducting fluids in electromagnetic fields. Examples of such fluids include plasmas, liquid metals, and salt water. The fluid flow equations are solved simultaneously with Maxwell's equations of electromagnetism.
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The FIR system for MST is very precise. The Faraday rotation angle for MST plasmas is typically within 5 degrees. To measure such small signal, we have achieved an accuracy of 0.06 degree. The temporal resolution is less than 1 microsecond.
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In general the physical properties of natural materials cause limitations. Most dielectrics only have positive permittivities, \epsilon_r > 0. Metals will exhibit negative permittivity, \epsilon_r < 0 at optical frequencies, and plasmas exhibit negative permittivity values in certain frequency bands. Pendry et al.
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Applications of coherent X-ray radiation include coherent diffraction imaging, research into dense plasmas (not transparent to visible radiation), X-ray microscopy, phase-resolved medical imaging, material surface research, and weaponry. A soft x-ray laser can perform ablative laser propulsion.
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Valentin Nikolayevich Klimov (Russian: Валентин Николаевич Kлимов) was a Russian theoretical physicist and mathematician. He was a co-developer of the RDS-37 (the Soviet Union's first two-stage thermonuclear device) and worked on statistical mechanics, plasmas and nuclear reactors.
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Jardine has taught courses focusing on magnetic fields and fluid dynamics. As well as supervising PhD students and postdocs, she currently teaches AS1001 The Solar System, PH4031 Fluids and AS5002 Magnetofluids and Space Plasmas at the University of St Andrews.
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Carr, M.; Khachan, J. (2013). "A biased probe analysis of potential well formation in an electron only, low beta Polywell magnetic field". Physics of Plasmas 20 (5): 052504. . The technology is relatively immature, however, and many scientific and engineering questions remain.
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The Penning–Malmberg trap, named after Frans Penning and John Malmberg, is an electromagnetic device used to confine large numbers of charged particles of a single sign of charge. Much interest in Penning–Malmberg (PM) traps arises from the fact that if the density of particles is large and the temperature is low, the gas will become a single-component plasma. While confinement of electrically neutral plasmas is generally difficult, single-species plasmas (an example of a non-neutral plasma) can be confined for long times in PM traps. They are the method of choice to study a variety of plasma phenomena.
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Depending on the laser and target parameters, these laser-generated plasmas may be compared to stars or planet interiors. The main research topics addressed on LULI2000 concern laser inertial fusion and all its physical components, fundamental physics of hot and dense plasmas and its applications in astrophysics and geophysics, or the physics and processing of materials. NANO2000, the nanosecond version of LULI2000, consists in two Nd:Glass laser chains, 200 mm in diameter, delivering each 1 kJ in nanosecond pulses at 1.05 μm wavelength. After frequency doubling or tripling, a large part of the energy may be converted to 0.53 μm or 0.35 μm.
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A thermal plasma is in thermal equilibrium, which is to say that the temperature is relatively homogeneous throughout the heavy particles (i.e. atoms, molecules and ions) and electrons. This is so because when thermal plasmas are generated, electrical energy is given to electrons, which, due to their great mobility and large numbers, are able to disperse it rapidly and by elastic collision (without energy loss) to the heavy particles.Note that non-thermal, or non-equilibrium plasmas are not as ionized and have lower energy densities, and thus the temperature is not dispersed evenly among the particles, where some heavy ones remain "cold".
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Instituto de Plasmas e Fusão Nuclear (IPFN) (Institute for Plasmas and Nuclear Fusion) is a research unit of Instituto Superior Técnico (IST), Lisbon, and a leading Portuguese institution in physics research. IPFN has the status of Associate Laboratory in the thematic areas of controlled nuclear fusion, plasma technologies and intense lasers, granted by the Portuguese Foundation for Science and Technology. IPFN was formally created in January 2008, as a result of the merging between the former research units Center for Nuclear Fusion and Center for Plasma Physics. As of 2015, almost 190 people work at IPFN, of which more than 100 are PhDs.
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After graduating in 1951, he started to work with nuclear fusion in the Theory Department headed by Mikhail Aleksandrovich Leontovich at LIPAN (Laboratory of Measuring Instruments of the USSR Academy of Sciences) as today's Russian Research Centre "Kurchatov Institute" was known at the time. He examined tokamaks stability and gave some parameter estimation for Soviet tokamak experiments. He also dealt with shock waves in plasmas and interaction of electromagnetic waves with plasmas. Later, he worked intensively on stellarators. In 1981 he became the successor of Leontovich as head of the Theory Department of Nuclear Fusion at the Kurchatov Institute.
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Horton has published or edited thirteen books on the theoretical basis for plasma containment and transport, and co-authored over 200 papers. A frequently cited book is “Chaos and Structures in Nonlinear Plasmas” . Beginning in 1987, due to significant declines in US government funding of fusion research as a potential alternative energy source, Horton began to pursue research in space weather and the prediction of solar storms using chaos and plasma theory to model the magnetosphere. The magnetosphere is characterized by an extremely collisionless plasma making available new plasma transport regimes well beyond those existing in laboratory plasmas.
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First studies on CNT showed the successful creation of magnetic surfaces with the simple four coil design. At sufficiently low neutral pressures and sufficiently high magnetic field strengths, the plasmas are essentially pure electron plasmas and are macroscopically stable with confinement times of up to 20 ms. Transport is driven by collisions with neutrals as well as E x B drift along insulating rods inserted into the plasma. At higher neutral pressures (10−7 Torr and above), an ion related instability is observed, with a frequency in the 10–50 kHz range, and a poloidal mode number m = 1\.
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Charles was born in Brittany, France, and studied engineering and applied physics at university in France. She completed a Ph. D in plasma physics and a bachelor of music in jazz from the Australian National University. Her specialist field is experimental expanding plasmas (hot ionized gases) and their use in electric propulsion, microelectronics and optoelectronics, astrophysical plasmas, and the development of fuel cells for the hydrogen economy. Charles invented the Helicon Double Layer Thruster, an electrode-less magneto-plasma space engine which could be used for keeping satellite stations in orbit, or interplanetary space travel for humans.
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Exceptions are the use of lower hybrid waves to heat and drive current in fusion plasmas, and the lower hybrid drift instability, which was thought to be an important determinant of transport in the Field-Reversed Configuration (but was not found experimentally).
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His fields of research pertained to quantum liquids, plasmas, solids, liquid helium and the kinetic theory of gases. Gross published over 80 scientific articles, including work with Bohm published 1949/1950 and work with P. L. Bhatnagar and M. Krook of 1954.
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Plasmas suitable for surface activation were also created using inductive heating with RF and microwave frequencies, spark discharges, resistive barrier dischargesM. Laroussi, I. Alexeff, J. P. Richardson, and F. F. Dyer, IEEE Trans. Plasma Sci. 30, 158 (2002) and various types of micro-discharges.
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Mode conversion of a fast magnetosonic wave to an ion cyclotron wave and ion Bernstein wave in the ion cyclotron range of frequencies (ICRF) can be used to heat electrons. Mode conversion heating is done at C-Mod using the ICRF in D(3He) plasmas.
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He was one of the first scientists to work with plasmas, and he was the first to call these ionized gases by that name because they reminded him of blood plasma. Langmuir and Tonks discovered electron density waves in plasmas that are now known as Langmuir waves. He introduced the concept of electron temperature and in 1924 invented the diagnostic method for measuring both temperature and density with an electrostatic probe, now called a Langmuir probe and commonly used in plasma physics. The current of a biased probe tip is measured as a function of bias voltage to determine the local plasma temperature and density.
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ICE carries 13 scientific instruments to measure plasmas, energetic particles, waves, and fields. , five were known to be functional. It does not carry a camera or imaging system. Its detectors measure high energy particles such as X- and gamma-rays, solar wind, plasma and cosmic particles.
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The Compact Toroidal Hybrid (CTH) is an experimental device at Auburn University that uses magnetic fields to confine high-temperature plasmas. CTH is a torsatron type of stellarator with an external, continuously wound helical coil that generates the bulk of the magnetic field for containing a plasma.
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Until now, resolutions of 30 nanometer are possible using the Fresnel zone plate lens which forms the image using the soft x-rays emitted from a synchrotron. Recently, the use of soft x-rays emitted from laser-produced plasmas rather than synchrotron radiation is becoming more popular.
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Plasmas are similar to pixels in size, shape, and reproductivity, although their corners are rounded like those of an infant. Actual infants are spherical. They use blank DVDs for many things, including coffee mugs. They represent the Mac user from the perspective of the PC user.
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Mario Acuña (March 12, 1940 - March 5, 2009), born in Córdoba, Argentina, was a research scientist at NASA Goddard Space Flight Center in the Space Plasmas and Planetary Magnetospheres Branches, and then as a Senior Astrophysicist. He was a major pioneer in the field of planetary magnetism.
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During the 1940s and 1950s, Alfvén developed magnetohydrodynamics which enables plasmas to be modeled as waves in a fluid. Alfvén received the 1970 Nobel Prize in Physics for this development. Alfvén later proposed this as the possible basis of plasma cosmology, although this theory has faced scrutiny.
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Sibylle Günter (born 20 April 1964) is a German theoretical physicist researching tokamak plasmas. Since February 2011, she has headed the Max Planck Institute for Plasma Physics. In October 2015, she was elected a member of the Academia Europaea in recognition of her contribution to research.
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At a meeting with the scientific attachés of the European embassies in Moscow in early February 2010 Mikhail Kovalchuk, Director of the Kurchatov Institute, announced that an initiative aimed at developing a fast paced joint research programme in nuclear fusion research was strongly supported by the Governments of Russia and Italy. The original proposal had been initiated earlier by Evgeny Velikhov (President of the Kurchatov Institute) and Bruno Coppi (Head of the High Energy Plasmas Undertaking, MIT) during the early developments of the Alcator C-Mod programme at MIT, where well known scientists of the Kurchatov Institute made key contributions to experiments that identified the unique confinement and purity properties of the high density plasmas produced by the high field Alcator machine. In effects this investigated, for the first time, physical processes leading to attain self-sustained fusion burning plasmas. The collaboration with the Kurchatov Institute is directed at the construction of the Ignitor machine, the first experiment proposed to achieve ignition conditions by nuclear fusion reactions on the basis of existing knowledge of plasma physics and available technologies.
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Ventzek was born in Columbus, Georgia in 1964. He received B.S. in Chemical Engineering from the University of New Brunswick and his PhD in Nuclear Engineering from the University of Michigan. His graduate research with Professor Ronald Gilgenbach dealt with the dynamics of laser ablation plasmas for materials processing.
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"Wendelstein 7-X achieves world record for fusion product" Phys.org, 25 June 2018 During the last experiments of 2018, the density reached 2 × 1020 particles/m3 at a temperature of 20 million degrees. With good plasma values, long-lasting plasmas with long discharge times of 100 seconds were obtained.
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In 1998, he received the American Physical Society's James Clerk Maxwell Prize for Plasma Physics for "fundamental contributions to plasma turbulence theory, stability and nonlinear theory of MHD and kinetic instabilities in plasmas, and for international leadership in research and teaching of plasma physics and controlled thermonuclear fusion physics".
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In magnetized plasmas, electrons will gyrate around magnetic field lines and emit cyclotron radiation. The frequency of the emission is given by the cyclotron resonance condition. In a sufficiently thick and dense plasma, the intensity of the emission will follow Planck's law, and only depend on the electron temperature.
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The X-ray luminosity is about 1 × 1029 erg/s and the emission varies with the pulsation period, suggesting a connection with the pulsation process. The peak X-ray emissions are in the 0.6–0.8 keV energy range, which occurs for plasmas with temperatures of 7–10 million K.
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After obtaining his doctorate, Scudder began working and teaching at Columbia University- Presbyterian Hospital. There he worked in blood transfusion and surgery. He became an assistant professor of clinical surgery at Columbia University in 1935. He worked on research centering on whole blood, then on fractionated blood and plasmas.
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Special courses are held from time to time, e.g., courses on microcomputers, lasers, plasmas, etc. The Institute publishes a quarterly journal (Jurnal Fizik Malaysia) to report up-to-date research findings in physics. A newsletter, Berita Fizik, is published quarterly to report current and future activities of the Institute.
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Troja completed a B.A. in physics and astronomy at University of Palermo in 2002. She completed a thesis, X-ray spectroscopy of He-like ions in optically thin astrophysical plasmas, under supervisor Giovanni Peres. Troja earned a M.Phil. in physics and astronomy at Palermo in 2005 under Fabio Reale.
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For laboratory and technical plasmas, the electrodes are most commonly tungsten or tantalum wires several thousandths of an inch thick, because they have a high melting point but can be made small enough not to perturb the plasma. Although the melting point is somewhat lower, molybdenum is sometimes used because it is easier to machine and solder than tungsten. For fusion plasmas, graphite electrodes with dimensions from 1 to 10 mm are usually used because they can withstand the highest power loads (also sublimating at high temperatures rather than melting), and result in reduced bremsstrahlung radiation (with respect to metals) due to the low atomic number of carbon. The electrode surface exposed to the plasma must be defined, e.g.
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Hence, they are not gases or plasmas; nor are they solids or liquids; they are most similar to dusty plasmas with small clusters in a gas. Though Rydberg matter can be studied in the laboratory by laser probing, the largest cluster reported consists of only 91 atoms, but it has been shown to be behind extended clouds in space and the upper atmosphere of planets. Bonding in Rydberg matter is caused by delocalisation of the high-energy electrons to form an overall lower energy state. The way in which the electrons delocalise is to form standing waves on loops surrounding nuclei, creating quantised angular momentum and the defining characteristics of Rydberg matter.
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Rydberg atoms form commonly in plasmas due to the recombination of electrons and positive ions; low energy recombination results in fairly stable Rydberg atoms, while recombination of electrons and positive ions with high kinetic energy often form autoionising Rydberg states. Rydberg atoms’ large sizes and susceptibility to perturbation and ionisation by electric and magnetic fields, are an important factor determining the properties of plasmas. Condensation of Rydberg atoms forms Rydberg matter, most often observed in form of long-lived clusters. The de-excitation is significantly impeded in Rydberg matter by exchange-correlation effects in the non-uniform electron liquid formed on condensation by the collective valence electrons, which causes extended lifetime of clusters.
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An oscillistor is a semiconductor device, consisting of a semiconductor specimen placed in magnetic field, and a resistor after a power supply. The device produces high-frequency oscillations, which are very close to sinusoidal. The basic principle of operation is the effect of spiral unsteadiness of electron-hole (p-n) plasmas.
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The result is an even, linear output, accurate even at extreme frequencies beyond any audible range. Such speakers are notable for accuracy and clarity, but not tremendous power because plasmas composed of tiny particles are unable to move large volumes of air. So these designs are more effective as tweeters.
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Kurt H. Becker is a physicist and entrepreneur. His research focuses on experimental atomic, chemical, and plasma physics. He is vice dean of research, innovation, and entrepreneurship at New York University Polytechnic School of Engineering. Becker holds seven patents regarding the generation and maintenance of atmospheric-pressure plasmas and their application.
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In the late 1980s, pure positron (i.e., antielectron) plasmas were created using the Penning–Malmberg trap technology. This, and advances in confining low-energy antiprotons, led to the creation of low-energy antihydrogen a decade later. These and subsequent developments have spawned a wealth of research with low- energy antimatter.
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Single negative (SNG) metamaterials have either negative relative permittivity (εr) or negative relative permeability (µr), but not both. They act as metamaterials when combined with a different, complementary SNG, jointly acting as a DNG. Epsilon negative media (ENG) display a negative εr while µr is positive. Many plasmas exhibit this characteristic.
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In a plasma, electrons are ripped away from their nuclei, forming an electron "sea". This gives it the ability to conduct electricity. Like a gas, plasma does not have definite shape or volume. Unlike gases, plasmas are electrically conductive, produce magnetic fields and electric currents, and respond strongly to electromagnetic forces.
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J. Hedditch, "Fusion in a Magnetically Shielded grid interial electrostatic fusion device", Physics of Plasmas, 2015. Hence, no fusor has ever come close to break-even energy output. The common sources of the high voltage are ZVS flyback HV sources and neon-sign transformers. It can also be called an electrostatic particle accelerator.
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William Henry Matthaeus (born 1951) is an American astrophysicist and plasma physicist. He is known for his research on turbulence in magnetohydrodynamics (MHD) (e.g. numerical simulations and kinetic theory) and astrophysical plasmas (e.g. solar wind and its fluctuations), for which he was awarded the 2019 James Clerk Maxwell Prize for Plasma Physics.
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He led the University of Glasgow research group in theory and modelling of solar and stellar plasmas. Brown used spacecraft data to investigate solar high energy particles and studied solar flares. He is perhaps best known in the community for the development of the Cold Thick Target Model for Solar X-Ray generation.
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This light can be detected and used to reconstruct the plasmas' behavior. This technique can be used to find its density and temperature. It is common in Inertial confinement fusion, Tokamaks, and fusors. In ICF systems, this can be done by firing a second beam into a gold foil adjacent to the target.
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Aside from these generic examples, it has turned out that under appropriate circumstances electric transport systems like plasmas or semiconductorsE. Schöll, Nonlinear Spatio-Temporal Dynamics and Chaos in Semiconductors, Cambridge University Press (2001) can be described in a reaction–diffusion approach. For these systems various experiments on pattern formation have been carried out.
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Oxygen plasma etching can be used for anisotropic deep-etching of diamond nanostructures by application of high bias in inductively coupled plasma/reactive ion etching (ICP/RIE) reactor. On the other hand the use of oxygen 0V bias plasmas can be used for isotropic surface termination of C-H terminated diamond surface.
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Other major experiments in the field include the pioneering START and MAST at Culham in the UK. NSTX studies the physics principles of spherically shaped plasmas—hot ionized gases in which nuclear fusion will occur under the appropriate conditions of temperature and density, which are produced by confinement in a magnetic field.
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She contributed to the book Multi-scale Dynamical Processes in Space and Astrophysical Plasmas. She continues to study coronal heating. In 2013 Browning was made chair of the Institute of Physics Plasma Physics Committee and the Solar Physics Council. Through the Solar Physics Council, Browning is a mentor for young solar physicists.
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Thomas Sunn Pedersen is the principal investigator of CNT, which studies several areas of theoretical and experimental non-neutral plasma physics. These include the equilibrium of non-neutral plasmas, transport and confinement, and ion-related instabilities. The CNT theory program is run by Pedersen and Prof. Allen Boozer, also at Columbia University.
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Single-component plasmas (SCP), which are a type of are a type of nonneutral plasma, have many uses, including studying a variety of plasma physics phenomena and for the accumulation, storage and delivery of antiparticles. Applications include the creation and study of antihydrogen, beams to study the interaction of positrons with ordinary matter and to create dense gases of positronium (Ps) atoms, and the creation of Ps- atom beams. The “rotating wall (RW) technique” uses rotating electric fields to compress SCP in PM traps radially to increase the plasma density and/or to counteract the tendency of plasma to diffuse radially out of the trap. It has proven crucial in improving the quality and hence utility of trapped plasmas and trap-based beams.
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However, in his first book on the subject, Klass argued that plasmas could explain most or all UFOs, even cases of alleged alien abduction. Klass's plasma hypothesis was not well received by those on either side of the UFO debate, who noted that Klass was using one unverified phenomenon—his hypothetical plasmas— to explain another unverified phenomenon—UFOs. The two engaged in a bitter, months-long debate, leveling a variety of charges and accusations at one another. Eventually, Klass wrote to McDonald's superiors at the U.S. Navy (McDonald was formally retired from the Navy, but often worked with the Office of Naval Research), questioning how McDonald could spend so much time on UFO research and still fulfill the requirements for his atmospheric research grant.
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Its plasma volume was about 8 m3 and it confined plasmas with densities on the order of 1020/m3. Image to right shows plasma in the MAST device, displaying its almost circular outer profile. The extensions off the top and bottom are plasma flowing to the ring divertors, a key feature of modern tokamak designs.
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In 1965, Hannes Alfvén proposed a "plasma cosmology" theory of the universe based in part on scaling observations of space plasma physics and experiments on plasmas in terrestrial laboratories to cosmological scales orders of magnitude greater.Hannes Alfvén, "On hierarchical cosmology" (1983) Astrophysics and Space Science , vol. 89, no. 2, Jan. 1983, pp. 313–324.
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Woods was the Nuffield Research Professor of Mechanical Engineering at the University of Technology at Sydney. He was elected a Fellow of Balliol College, Oxford in 1961 where he researched the theory of magnetically-confined hot plasmas. Woods was professor of mathematics at the University of Oxford from 1970 until his retirement in 1990.
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A microwave system uses amplifiers that output up to 200 watts of power radio frequency (RF) power to produce the arc that generates plasma. Most solutions work at 2.45 GHz. A new technology provides ignition and highly efficient operation with the same electronic and couple network. This kind of atmospheric-pressure plasmas is different.
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I. Software Comparison and Recommended Practices, Astrophys. J. 666, 576. co- invention with colleague Charles Kankelborg of the fluxon semi-Lagrangian approach to numerical MHD modeling;Fluxon Modeling of Low-Beta Plasmas, J. Atmospheric & Solar-Terrestrial Physics, 69, 116. and pioneering work on quantitative remote sensing of the solar wind via Thomson scattered light.
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Ions can be created in an inductively coupled plasma, which is a plasma source in which the energy is supplied by electrical currents which are produced by electromagnetic induction, that is, by time- varying magnetic fields.A. Montaser and D. W. Golightly, eds. Inductively Coupled Plasmas in Analytical Atomic Spectrometry, VCH Publishers, Inc., New York, 1992.
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Physics of Fluids A, Physics of Fluids B, and Physics of Fluids were ranked 3, 4, and 6, respectively based on their citation impact from 1981–2004 within the category of journals on the physics of fluids and plasmas. According to the Journal Citation Reports, the journal has a 2019 impact factor of 3.514.
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The single most important property of a plasma is its stability. MHD and its derived equilibrium equations offer a wide variety of plasmas configurations but the stability of those configurations have not been challenged. More specifically, the system must satisfy the simple condition where ? is the change in potential energy for degrees of freedom.
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Gyrotrons are used for many industrial and high-technology heating applications. For example, gyrotrons are used in nuclear fusion research experiments to heat plasmas and also in manufacturing industry as a rapid heating tool in processing glass, composites, and ceramics, as well as for annealing (solar and semiconductors). Military applications include the Active Denial System.
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Big Brown Box is an online retailer of audio visual products, based in Sydney, Australia. It is an online subsidiary of the Winning family, which own and run Winning Appliances and Appliances Online. The company specialises in selling LCD, LED and plasmas TVs, Hi-Fi systems, Blu-ray and DVD, home theatre units and radios.
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With Bruno Coppi and others he investigated dissipative instabilities in plasmas. With Ira B. Bernstein and Martin Kruskal he did research on BGK modes (nonlinear wave solutions in plasma physics). In the 1970s he worked on Hamiltonian dynamics in chaos theory. In 1979 he published Greene's criterion for the collapse of tori in KAM theory.
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She joined the University of Manchester in 2004, where she works on the interactions between plasmas and magnetic fields. She is particularly interested in solar flares. In 2009, Browning was promoted to professor at the Jodrell Bank Centre for Astrophysics. She served as editor of the Journal of Geophysical Research from 2010 to 2013.
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Research at Princeton University in using Z-Pinch devices as a potential space propulsion device led to the exploration of the resulting x-ray production. This led directly to the original SHIVA effort in 1971.P.J. Turchi and W.L. Baker, Generation of high- energy plasmas by electromagnetic implosion, J. Appl.Phys., Vol. 44, 11, (1973).
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Effects which are essentially kinetic and not captured by fluid models include double layers, Landau damping, a wide range of instabilities, chemical separation in space plasmas and electron runaway. In the case of ultra-high intensity laser interactions, the incredibly short timescales of energy deposition mean that hydrodynamic codes fail to capture the essential physics.
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Protonated molecular oxygen or just protonated oxygen is an ion with formula HO2+. It is formed when hydrogen containing substances combust, and exists in the ionosphere, and in plasmas that contain oxygen and hydrogen. Oxidation by O2 in superacids could be by way of the production of protonated molecular oxygen. It is the conjugate acid of dioxygen.
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In low temperature plasmas, in which the probe does not get hot, surface contamination may become an issue. This effect can cause hysteresis in the I-V curve and may limit the current collected by the probe. A heating mechanism or a glow discharge plasma may be used to clean the probe and prevent misleading results.
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His research showed that unstable plasmas, which can be guided with a vacuum, become more stable when confined to less than 1mm, allowing for the manipulation of chemicals within. This research resulted in 7 patents and formed the basis of 2 startup companies, PlasmaSol and Plasmion. PlasmaSol was sold to Stryker Instruments for $18,000,000 in 2005.
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High temperature plasmas used for nuclear fusion energy research also contain HCI generated by the plasma-wall interaction (see Tokamak). In the laboratory, HCI are investigated by means of heavy ion particle accelerators and electron beam ion traps. They might have applications in improving atomic clocks, advances in quantum computing, and more accurate measurement of fundamental physical constants.
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In 1984, he became director of the Max Planck Institute for Extraterrestrial Physics. Since 2011, he has been on the scientific advisory board of Bauman University in Moscow. In the same year, he was co-founder of the company terraplasma in Garching near Munich, which develops devices and processes that use cold plasmas for wound healing, among other things.
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BGK modes have been generalized to quantum mechanics, in which the solutions (called quantum BGK modes) solve the quantum equivalent of the Vlasov–Poisson system known as the Wigner–Poisson system, with periodic boundary conditions. The solutions for the QBGK modes were put forth by Lange et al. in 1996, with potential applications to quantum plasmas.
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Descoeudres, Antoine (2006). Characterization of electrical discharge machining plasmas. Thèse EPFL, no 3542. To obtain a specific geometry, the EDM tool is guided along the desired path very close to the work; ideally it should not touch the workpiece, although in reality this may happen due to the performance of the specific motion control in use.
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An electron beam, for example, has only negative charges. The density of a non- neutral plasma must generally be very low, or it must be very small, otherwise, it will be dissipated by the repulsive electrostatic force. In astrophysical plasmas, Debye screening prevents electric fields from directly affecting the plasma over large distances, i.e., greater than the Debye length.
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The flat plate of propellant formed a cigar-shaped explosion aimed at the pusher plate. The plasma would cool to as it traversed the distance to the pusher plate and then reheat to as, at about 300 microseconds, it hits the pusher plate and is recompressed. This temperature emits ultraviolet light, which is poorly transmitted through most plasmas.
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While state-of-the-art 193 nm ArF excimer lasers offer intensities of 200 W/cm2, lasers for producing EUV-generating plasmas need to be much more intense, on the order of 1011 W/cm2. A state-of-the-art ArF immersion lithography 120 W light source requires no more than 40 kWT. Asayama et al., Proc.
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The brightness of an atomic spectral line emitted by atoms and ions in a gas (or plasma) can depend on the gas's temperature and pressure. Due to the completeness and accuracy of modern collisional radiative models the temperature and density of plasmas can be measured by taking ratios of the emission intensities of various atomic spectral lines.
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In very hot plasmas (as in magnetic fusion experiments), light elements are fully ionized and don't emit line radiation. When a beam of neutral atoms is fired into the plasma, electrons from beam atoms are transferred to hot plasma ions, which form hydrogenic ions which promptly emit line radiation. This radiation is analyzed for ion density, temperature, and velocity.
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This observation would become the basis for a fusion approach known as the Levitated dipole. In tokamaks, the Tore Supra was under construction over the middle of the eighties (1983 to 1988). This was a tokamak built in Cadarache, France. In 1983, the JET was completed and first plasmas achieved. In 1985, the Japanese tokamak, JT-60 was completed.
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Once an atom is heated above its ionization energy, its electrons are stripped away (it is ionized), leaving just the bare nucleus (the ion). The result is a hot cloud of ions and the electrons formerly attached to them. This cloud is known as plasma. Because the charges are separated, plasmas are electrically conductive and magnetically controllable.
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In this regime the ionized electron population of the stagnated flow becomes significant, and the electrons must be modeled separately. Often the electron temperature is handled separately from the temperature of the remaining gas components. This region occurs for freestream flow velocities around 3-4 km/s. Gases in this region are modeled as non- radiating plasmas.
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Retrieved 17 August 2017.Cary B Forest. Department of Physics, University of Wisconsin-Madison. Retrieved 17 August 2017. His APS fellowship citation in 2008 read that it was awarded "for broad and fundamental advances in plasma physics, from electromagnetic wave propagation and transport processes in fusion plasmas to dynamo effects underlying geomagnetic and astrophysical magnetic field generation".
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Afterwards, much of the universe reionized after the first quasars formed. Studying astrophysical plasmas is part of mainstream academic astrophysics. Though plasma processes are part of the standard cosmological model, current theories indicate that they might have only a minor role to play in forming the very largest structures, such as voids, galaxy clusters and superclusters.
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102B pp. 11-21, January 1995 Rotman used a grid of three-dimensional thin wires to simulate plasmas with dielectric constants less than one. It is considered today as a classic paper as it showed the potential of artificial dielectrics. In this paper, Rotman reached equations in a relatively simple manner which were derived again twenty years later.
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Ion cyclotron resonance heating (or ICRH) is a technique in which electromagnetic waves with frequencies corresponding to the ion cyclotron frequency is used to heat up a plasma. The ions in the plasma absorb the electromagnetic radiation and as a result of this, increase in kinetic energy. This technique is commonly used in the heating of tokamak plasmas.
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Dusty plasmas are often studied in laboratory setups. The dust particles can be grown inside the plasma, or microparticles can be inserted. Usually, a low temperature plasma with a low degree of ionization is used. The microparticles then become the dominant component regarding the energy and momentum transport, and they can essentially be regarded as single-species system.
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He has studied multiple subfields of plasma physics including: plasma diagnostics, accelerator concepts with plasmas, helicon plasma sources, plasma instabilities of laser interaction, Langmuir probes, resistive drift waves, anomalous diffusion, and Q-machines. He wrote a very well known and highly regarded Introductory plasma physics textbook (see below). During Chen's career, he has published over 240 technical papers.
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Rose wrote over 150 articles ranging from high technology to theology. He was author of the widely cited Plasmas and Controlled Fusion, with Melville Clark, which became the standard textbook in the field of fusion energy. In 1975 Rose taught the MIT Nuclear Engineering Department's first course on sustainable energy. He testified to Congress in 1977.
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One of challenges is the application of non-thermal plasmas directly on the surface of human body or on internal organs. Whereas for surface modification and biological decontamination both low-pressure and atmospheric pressure plasmas can be used, for direct therapeutic applications only atmospheric pressure plasma sources are applicable. The high reactivity of plasma is a result of different plasma components: electromagnetic radiation (UV/VUV, visible light, IR, high- frequency electromagnetic fields, etc.) on the one hand and ions, electrons and reactive chemical species, primarily radicals, on the other. Besides surgical plasma application like argon plasma coagulation (APC),Zenker M, Argon plasma coagulation, GMS Krankenhaushyg Interdiszip 2008; 3(1):Doc15 (20080311) which is based on high-intensity lethal plasma effects, first and sporadic non-thermal therapeutic plasma applications are documented in literature.
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A world effort was triggered in the 1960s to study magnetohydrodynamic converters in order to bring MHD power conversion to market with commercial power plants of a new kind, converting the kinetic energy of a high velocity plasma into electricity with no moving parts at a high efficiency. Research was also conducted in the field of supersonic and hypersonic aerodynamics to study plasma interaction with magnetic fields to eventually achieve passive and even active flow control around vehicles or projectiles, in order to soften and mitigate shock waves, lower thermal transfer and reduce drag. Such ionized gases used in "plasma technology" ("technological" or "engineered" plasmas) are usually weakly ionized gases in the sense that only a tiny fraction of the gas molecules are ionized. These kinds of weakly ionized gases are also nonthermal "cold" plasmas.
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DBD for medical applicationsKuchenbecker M, Bibinov N, Kaemlimg A, Wandke D, Awakowicz P, Viöl W, J. Phys. D: Appl. Phys. 42 (2009) 045212 (10pp) such as for the inactivation of bacteria,Laroussi, M., Richardson, J. P., and Dobbs, F. C. “ Effects of Non- Equilibrium Atmospheric Pressure Plasmas on the Heterotrophic Pathways of Bacteria and on their Cell Morphology”, Appl. Phys. Lett. 81, pp.
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In recent years MPE has hosted an average of about 50 guest scientists each year. During the early years, the scientific work at the Institute concentrated on the investigation of extraterrestrial plasmas and the magnetosphere of the earth. This work was performed with measurements of particles and electromagnetic fields as well as a specially developed ion- cloud technique using sounding rockets.
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The James Clerk Maxwell Prize in Plasma Physics 2011 was awarded to Professor Gregor Morfill, director at the MPE. With the award, the American Physical Society (APS) recognizes Morfill's pioneering and seminal contributions to the field of dusty plasmas. The bestowal of the award took place at the annual meeting of the Division of Plasma Physics in Salt Lake City in November 2011.
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The firehose instability derives its name from a similar instability in magnetized plasmas. However, from a dynamical point of view, a better analogy is with the Kelvin–Helmholtz instability, or with beads sliding along an oscillating string.In spite of its name, the firehose instability is not related dynamically to the oscillatory motion of a hose spewing water from its nozzle.
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7, No. 6, 2000, pp. 2693–2703.Wells, A.A., "Current Flow Across a Plasma Double Layer in a Hollow Cathode Ion Thruster," AIAA 9th Electric Propulsion Conference, AIAA, 1972, pp. 1–15.Andrews, J.G., and Allen, J.E., "Theory of a Double Sheath Between Two Plasmas," Proceedings of the Royal Society of London Series A, Vol. 320, No. 1543, 1971, pp. 459–472.
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Kinetic models describe the particle velocity distribution function at each point in the plasma and therefore do not need to assume a Maxwell–Boltzmann distribution. A kinetic description is often necessary for collisionless plasmas. There are two common approaches to kinetic description of a plasma. One is based on representing the smoothed distribution function on a grid in velocity and position.
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756–763Ergun, R. E., et al. "Parallel electric fields in the upward current region of the aurora: Indirect and direct observations" (2002) Physics of Plasmas, Volume 9, Issue 9, pp. 3685–3694 still invoke quasi-static parallel electric fields as net accelerators of auroral electrons, citing interpretations of transient observations of fields and particles as supporting this theory as firm fact.
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Because of the extremely high energies involved, quark-antiquark pairs are produced by pair production and thus QGP is a roughly equal mixture of quarks and antiquarks of various flavors, with only a slight excess of quarks. This property is not a general feature of conventional plasmas, which may be too cool for pair production (see however pair instability supernova).
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Omar Hurricane is a physicist at Lawrence Livermore National Laboratory, in the thermonuclear and inertial confinement fusion design division. Prior to Lawrence Livermore, he worked at the UCLA Institute of Plasma & Fusion Research. His research focuses on weapons physics, high energy density physics (HEDP) science, the theory of plasmas, and plasma instability. He has published widely in journals and conference papers.
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EBox stands for Electronics Box. JADE-E is for detecting electrons from 0.1 to 100 keV, and there are three JADE-E sensors on Juno. JADE-I is for detecting ions from 5 eV to 50 keV. It is designed to return data in situ on Jupiter's auroral region and magnetospheric plasmas, by observing electrons and ions in this region.
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Panoramic view of Institute for Plasma Research main building. The Institute for Plasma Research (IPR) is an autonomous physics research institute located in India. The institute is involved in research in aspects of plasma science including basic plasma physics, research on magnetically confined hot plasmas and plasma technologies for industrial applications. It is a large and leading plasma physics organization in India.
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The first plasma was achieved in January 1999. The ET is capable of producing a plasma current of 45 kiloamperes and can produce a core electron plasma temperature of 300 eV.Initial Plasmas in the Electric Tokamak. Four sets of independent coils are necessary for OH (ohmic heating) current drive, vertical equilibrium field, plasma elongation and plasma shaping (D or reverse-D).
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MTF is not the first "new approach" to fusion power. When ICF was introduced in the 1960s, it was a radical new approach that was expected to produce practical fusion devices by the 1980s. Other approaches have encountered unexpected problems that greatly increased the difficulty of producing output power. With MCF, it was unexpected instabilities in plasmas as density or temperature was increased.
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The mission of the satellite was to measure the interaction of space plasmas with the satellite's high-voltage surfaces. The Titan performed normally during launch, but the Centaur's engines failed to start. With the Centaur in free-fall, a safety destruct command was issued at 748 seconds after liftoff. The failure was traced to the Centaur boost pumps, but the cause remained unclear.
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Louis John Lanzerotti (born April 16, 1938) is a Distinguished Research Professor of physics in the Center for Solar-Terrestrial Research at New Jersey Institute of Technology (NJIT) in Newark, New Jersey. His principal research interests have included space plasmas, geophysics, and engineering problems related to the impacts of atmospheric and space processes and the space environment on space and terrestrial technologies.
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This permitted the first complete theory of short- wave radio propagation. Maurice V. Wilkes and J. A. Ratcliffe researched the topic of radio propagation of very long radio waves in the ionosphere. Vitaly Ginzburg has developed a theory of electromagnetic wave propagation in plasmas such as the ionosphere. In 1962, the Canadian satellite Alouette 1 was launched to study the ionosphere.
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The sun is an MHD system that is not well understood. Magnetohydrodynamics (MHD; also magneto-fluid dynamics or hydromagnetics) is the study of the magnetic properties and behaviour of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals, salt water, and electrolytes. The word "magnetohydrodynamics" is derived from magneto- meaning magnetic field, hydro- meaning water, and dynamics meaning movement.
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From 1999 to 2013, MAST ran 30471 plasmas (in pulses up to 0.5 sec). It confirmed the increased operating efficiency of spherical tokamaks as shown on START – especially demonstrating a high beta (ratio of plasma pressure to the pressure from the confining magnetic field). MAST also performed valuable experiments on controlling and mitigating instabilities at the edge of the plasma – so-called Edge Localised Modes or ELMs.
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He also carried out investigations on ion cyclotron heating and mode conversion processes in multi-ion species fusion plasmas. Phase-contrast imaging (PCI) was developed by Porkolab's group both for use at the Alcator C-Mod tokamak and the DIII-D tokamak of General Atomics in San Diego. In recent years, PCI measurements contributed to the advanced in understanding of turbulence and Alfvén wave phenomena.
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His previous work on the density- functional theory of dense plasmasDensity Functional Theory, Ed. E. K. U. Gross and R. M. Dreizler, Plenum, New York, 1995, p635 is now well-established in the NPA model. It has led to the development of methods for the first- principles evaluation of the equation of state, and the transport properties of dense plasmas.Dense Plasmas: Phys. Rev. E .
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Nahar has published extensively on radiative and collisional atomic processes in astrophysical and laboratory plasmas, including Photoionization, electron-ion recombination,"Electron-Ion Recombination Rate Coefficients, Photoionization Cross Sections, and Ionization Fractions for Astrophysically Abundant Elements. I. Carbon and Nitrogen", S. N. Nahar and A. K. Pradhan, in The Astrophysical Journal, vol. 111, no. 339, 1997 photo- excitations and de-excitations, and electron-ion scattering.
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A "shot" using deuterium is being prepared at the operator's station. The reactor can be seen through the window. ZETA started operation in mid-August 1957, initially with hydrogen. These runs demonstrated that ZETA was not suffering from the same stability problems that earlier pinch machines had seen and their plasmas were lasting for milliseconds, up from microseconds, a full three orders of magnitude improvement.
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This field, through the Lorentz force, will act to compress the conductor. In the case of a plasma, the force would collapse it into a thin filament, "pinching" it. Since the current had to be very large, pinch devices made no attempt to confine the plasmas for extended periods. They would attempt to reach fusion conditions quickly and then extract power from the resulting hot products.
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Surindar Kumar Trehan (S.K. Trehan) was an Indian mathematician who specialised in non-linear stability in magnetohydrodynamics. He was awarded in 1976 the Shanti Swarup Bhatnagar Prize for Science and Technology, the highest science award in India, in the mathematical sciences category. Prof. Trehan has done significant work on stability of force-free magnetic fields, stability of jets and cylinders and stability of inhomogeneous plasmas.
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The integral of 1/b thus yields the logarithm of the ratio of the upper and lower cut-offs. This number is known as the Coulomb logarithm and is designated by either \ln \Lambda or \lambda. It is the factor by which small-angle collisions are more effective than large-angle collisions. For many plasmas of interest it takes on values between 5 and 15.
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O'Neil is a fellow of the American Physical Society. In 1971, O'Neil was awarded the Sloan Research Fellowship by the Alfred P. Sloan Foundation. From 1979 to 1983, he was co-editor of the Physical Review Letters. In 1991, he received the John Dawson Award for Excellence in Plasma Physics Research with John Malmberg and Charles Driscoll for their studies of non-neutral plasmas.
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Thermal plasmas are generated in plasma torches by direct current (DC), alternating current (AC), radio-frequency (RF) and other discharges. DC torches are the most commonly used and researched, because when compared to AC: "there is less flicker generation and noise, a more stable operation, better control, a minimum of two electrodes, lower electrode consumption, slightly lower refractory [heat] wear and lower power consumption".
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He is currently a Co-Investigator in the WIND/SWE experiment of the International Solar Terrestrial Program (ISTP) and the Space Physics Theory Program grant entitled The Role of Turbulence in Heliospheric Plasmas. Figueroa-Viñas has participated in the organizing committee of "La Conferencia Espacial de las Américas" held in Costa Rica, Chile and Uruguay. He is the recipient of the NASA Special Service Award.
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However large volumes of gas generally behave as dielectrics. Examples of these are regions of the Earths atmosphere, which gradually reduce in density at increasing altitudes up to 10 to 20 km. At greater altitudes from about 50 km to 200 km various ionospheric layers also behave like dielectrics and are heavily dependent on the influence of the Sun. Ionospheric layers are not gases but plasmas.
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However, the existence of charged particles causes the plasma to generate, and be affected by, magnetic fields. This can and does cause extremely complex behaviour, such as the generation of plasma double layers, an object that separates charge over a few tens of Debye lengths. The dynamics of plasmas interacting with external and self-generated magnetic fields are studied in the academic discipline of magnetohydrodynamics.
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Because of their sizable temperature and density ranges, plasmas find applications in many fields of research, technology and industry. For example, in: industrial and extractive metallurgy, surface treatments such as plasma spraying (coating), etching in microelectronics, metal cutting and welding; as well as in everyday vehicle exhaust cleanup and fluorescent/luminescent lamps, fuel ignition, while even playing a part in supersonic combustion engines for aerospace engineering.
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A ball-pen probe is novel technique used to measure directly the plasma potential in magnetized plasmas. The probe was invented by Jiří Adámek in the Institute of Plasma Physics AS CR in 2004. The ball-pen probe balances the electron saturation current to the same magnitude as that of the ion saturation current. In this case, its floating potential becomes identical to the plasma potential.
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An eruptive prominence on the surface of the sun. The plasma is the most common state of the baryonic matter in the Universe (99%). Most of a star, the interplanetary and interstellar medium, and the ionosphere, are plasmas. The plasma can also be generated in terrestrial laboratories for industrial applications such as producing surface coatings, precision cuts in lamps, micro-motors, and plasma reactors.
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The L'Institut de Recherche en Astrophysique et Planétologie (IRAP), formerly the Centre d'Etude Spatiale des Rayonnements (CESR), is a French laboratory of space astrophysics. It is located in Toulouse. The center's main areas of investigation are: space plasmas, planetology, the high energy universe, and the cold universe. The center is jointly operated by CNRS and Toulouse's Paul Sabatier University, and was opened on 1 January 2011.
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Microwave induced plasma ion sources are capable of exciting electrodeless gas discharges to create ions for trace element mass spectrometry. A microwave plasma is a type of plasma, that has high frequency electromagnetic radiation in the GHz range. It is capable of exciting electrodeless gas discharges. If applied in surface-wave- sustained mode, they are especially well suited to generate large-area plasmas of high plasma density.
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LULI : Laboratoire pour l'Utilisation des Lasers Intenses ('LULI) LULI webpage is a scientific research laboratory specialised in the study of plasmas generated by laser-matter interaction at high intensities and their applications. The main missions of LULI include: (i) Research in Plasma Physics, (ii) Development and operation of high-power high-energy lasers and experimental facilities, (iii) student formation in Plasma Physics, Optics and Laser Physics.
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In 1986, he was inducted a fellow of the American Physical Society. In 1988, he became a Sloan Research Fellow. In 2011, Diamond was awarded the Hannes Alfvén Prize by the European Physical Society for "laying the foundations of modern numerical transport simulations and key contributions on self-generated zonal flows and flow shear decorrelation mechanisms which form the basis of modern turbulence in plasmas".
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Post-mold surface modification, usually with oxygen-rich plasmas, is often done to introduce polar groups. Much of modern biomedical research relies on the use of such products; they, therefore, play a critical role in pharmaceutical research. Thin sheets of polystyrene are used in polystyrene film capacitors as it forms a very stable dielectric, but has largely fallen out of use in favor of polyester.
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The Lorentz force then bends the electron trajectories with the result that upward-moving-ev x B electrons congregate at B and downward-moving ones at A. The resulting current j = -en ve sheets generate magnetic field that enhances the original field and thus perturbation grows. Weibel instability is also common in astrophysical plasmas, such as collisionless shock formation in supernova remnants and \gamma-ray bursts.
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These interchange motions also occur in plasmas that are in a system with a large centrifugal force. In a cylindrically symmetric plasma device, radial electric fields cause the plasma to rotate rapidly in a column around the axis. Acting opposite to the gravity in the simple model, the centrifugal force moves the plasma outward where the ripple-like perturbations (sometimes called “flute” instabilities) occur on the boundary.
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Hammer, Hartman et al. showed that spheromaks could be accelerated to extremely high velocities using a railgun, which led to several proposed uses. Among these was the use of such plasmas as "bullets" to fire at incoming warheads with the hope that the associated electric currents would disrupt their electronics. This led to experiments on the Shiva Star system, although these were cancelled in the mid-1990s.
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The RW technique was first developed by Huang et al., to compress a magnetized Mg+ plasma. The technique was soon thereafter applied to electron plasmas, where a segmented electrode, such as that described above, was used to couple to waves (Trivelpiece-Gould modes) in the plasma. The technique was also used to phase- lock the rotation frequency of laser cooled single-component ion crystals.
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The brightness of an atomic spectral line emitted by atoms in a gas (or plasma) can be proportional to the gas's temperature, pressure or a weighted sum of both. Due to the completeness and accuracy of collisional radiative models for helium the temperature and density of plasmas which have helium present can be measured by taking ratios of the emission intensities of various atomic spectral lines.
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The use of a high-dielectric waveguide allowed the sustaining of plasmas at much lower powers—down to 100 W in some instances. It also allowed the use of conventional gas-discharge lamp fill materials which removed the need to spin the bulb. The only issue with the ceramic waveguide was that much of the light generated by the plasma was trapped inside the opaque ceramic waveguide.
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Lanzerotti has authored or co-authored of more than 500 refereed publications, contributing to research that includes studies of space plasmas and geophysics, and engineering problems related to the impact of atmospheric and space processes (a.k.a. "space weather") on terrestrial and spaceborne technologies. Lanzerotti co-authored a book on radiation belt physics and has co-edited four books. He has eight patents issued or filed.
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This configuration can be sustained with comparatively lower fields than that of a tokamak of similar power density. One of the disadvantages of this configuration is that it tends to be more susceptible to non-linear effects and turbulence. This makes it a useful system for studying non-ideal (resistive) magnetohydrodynamics. RFPs are also used in studying astrophysical plasmas, which share many common features.
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These include the effects of Hall physics, electron pressure gradients, finite Larmor Radii in the particle gyromotion, and electron inertia. ; Two-fluid : Two-fluid MHD describes plasmas that include a non- negligible Hall electric field. As a result, the electron and ion momenta must be treated separately. This description is more closely tied to Maxwell's equations as an evolution equation for the electric field exists.
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The efficiency of the direct energy conversion in MHD power generation increases with the magnetic field strength and the plasma conductivity, which depends directly on the plasma temperature, and more precisely on the electron temperature. As very hot plasmas can only be used in pulsed MHD generators (for example using shock tubes) due to the fast thermal material erosion, it was envisaged to use nonthermal plasmas as working fluids in steady MHD generators, where only free electrons are heated a lot (10,000–20,000 kelvins) while the main gas (neutral atoms and ions) remains at a much lower temperature, typically 2500 kelvins. The goal was to preserve the materials of the generator (walls and electrodes) while improving the limited conductivity of such poor conductors to the same level as a plasma in thermodynamic equilibrium; i.e. completely heated to more than 10,000 kelvins, a temperature that no material could stand.
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Many advanced tokamak designs routinely hit numbers on the order of ~ 1 × 1021 keV • seconds / m³, see "Fusion Triple Product and the Density Limit of High-Density Internal Diffusion Barrier Plasmas in LHD", 35th EPS Conference on Plasma Phys. Hersonissos, 9–13 June 2008 Doing so, however, requires massive amount of power in the magnetic system, and any way to reduce this improves the overall energy efficiency of the system.
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Sources can be adapted in many ways, but the lists below give the general uses of a number of sources. Of these, flames are the most common due to their low cost and their simplicity. Although significantly less common, inductively-coupled plasmas, especially when used with mass spectrometers, are recognized for their outstanding analytical performance and their versatility. For all atomic spectroscopy, a sample must be vaporized and atomized.
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An electric dipole antenna was used to study the electric fields of plasmas, while two search coil magnetic antennas studied the magnetic fields. The electric dipole antenna was mounted at the tip of the magnetometer boom. The search coil magnetic antennas were mounted on the high-gain antenna feed. Nearly simultaneous measurements of the electric and magnetic field spectrum allowed electrostatic waves to be distinguished from electromagnetic waves.
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Adolfo Figueroa-Viñas, Ph.D. is the first Puerto Rican astrophysicist at the National Aeronautics and Space Administration (NASA) and is an expert in solar and space plasma physics at the Heliophysics Science Division. As a staff scientist his research interests include studying plasma kinetic physics and magnetohydrodynamics of the solar wind, heliosphere, shock waves, MHD and kinetic simulation of plasma instabilities, and turbulent processes associated with space, solar and astrophysical plasmas.
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The most abundant ion in space plasmas is the hydrogen ion—a bare proton with no excitable electrons to emit visible photons. The occasional visibility of other plasma ions is not sufficient for imaging purposes. ENAs are created in charge-exchange collisions between hot solar plasma ions and a cold neutral background gas. These charge-exchange processes occur with high frequency in planetary magnetospheres and at the edge of the heliosphere.
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Plasma sources used in plasma medicine are typically "low temperature" plasma sources operated at atmospheric pressure. In this context, low temperature refers to temperatures similar to room temperature, usually slightly above. There is a strict upper limit of 50 °C when treating tissue to avoid burns. The plasmas are only partially ionized, with less than 1 ppm of the gas being charged species, and the rest composed of neutral gas.
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Valery A. Godyak (born June 8, 1941 in Czernowitz) is a Russian-American physicist who specializes in plasma physics. As a scientist, he made fundamental contributions to the understanding of radio frequency (RF) induced discharges in plasmas as well as in associated nonlinear phenomena. As an industrial physicist, he developed induction lamps such as the Icetron-Endura RF lamp and received honors from companies such as Osram Sylvania and Siemens.
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At Oxford, he teaches astrophysical gas dynamics and supervises postdoctoral researchers and students. Balbus' research is in theoretical astrophysics. He has made discoveries related to gravitational instability in the interstellar medium and several contributions to the theory of thermal processes in magnetised dilute plasmas. He is best known for a 1991 paper, published with former colleague John F. Hawley, describing what is now known as magnetorotational instability (MRI).
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Plasma oscillations, also known as Langmuir waves (after Irving Langmuir), are rapid oscillations of the electron density in conducting media such as plasmas or metals in the ultraviolet region. The oscillations can be described as an instability in the dielectric function of a free electron gas. The frequency only depends weakly on the wavelength of the oscillation. The quasiparticle resulting from the quantization of these oscillations is the plasmon.
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Furthermore, all the distant stars, and much of interstellar space or intergalactic space is also likely filled with plasma, albeit at very low densities. Astrophysical plasmas are also observed in Accretion disks around stars or compact objects like white dwarfs, neutron stars, or black holes in close binary star systems.Mészáros, Péter (2010) The High Energy Universe: Ultra-High Energy Events in Astrophysics and Cosmology, Publisher: Cambridge University Press, , p. 99 .
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Kunio Sawaya (born c.1950) is a Japanese engineer and researcher, currently a professor at the Laboratory of Electromagnetic Wave Engineering in Tohoku University, Sendai. Sawaya obtained his first degree, his master's degree and his doctorate from Tohoku University during the 1970s. He was named Fellow of the Institute of Electrical and Electronics Engineers (IEEE) in 2012 for contributions to computational electromagnetics and characterization of antennas in plasmas.
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Karl Krushelnick from the University of Michigan, was awarded the status of Fellow in the American Physical Society, after he was nominated by the university's Division of Plasma Physics in 2007, for pioneering contributions to experimental high-intensity laser plasma physics including the production of high-quality relativistic electron beams, energetic proton beams and the development of techniques to measure very large magnetic fields in intense laser-produced plasmas.
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Graphic illustrating the formation of a Bose-Einstein condensate Quantities of atoms are found in different states of matter that depend on the physical conditions, such as temperature and pressure. By varying the conditions, materials can transition between solids, liquids, gases and plasmas. Within a state, a material can also exist in different allotropes. An example of this is solid carbon, which can exist as graphite or diamond.
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High density plasmas can also be generated by a DC discharge in an electron-rich environment, obtained by thermionic emission from heated filaments. The voltages required by the arc discharge are of the order of a few tens of volts, resulting in low energy ions. The high density, low energy plasma is exploited for the epitaxial deposition at high rates in Low-Energy Plasma-Enhanced chemical vapor deposition reactors.
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He received his Ph.D. in plasma physics first in Paris, and then in Iaşi, Romania. Thus, the history of plasma physics in Romania began in 1923 with the defense of the first PhD thesis in physics at the University of Iaşi by Theodor V. Ionescu, under the guidance of Professor Petru Bogdan. Th. V. Ionescu carried out the first experimental studies in Romania of the physics of ionized gases/plasmas.
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KCT was first described by Dr. Joel Margolis in 1958. Later on it was found to be very sensitive to lupus anticoagulants but was only reliable when test plasmas were mixed with normal plasma in various proportions. It became the preferred method for lupus anticoagulant testing after Dr Wilhelm Lubbe showed it to be a good marker for recurrent fetal loss.Lubbe, W.F.; Butler, W.S.; Palmer, S.J.; Liggins, G.C. (1983).
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Minority heating is the most common scenario used at C-Mod. The ICRF heating system operates at 80 MHz in D(H) plasmas. This frequency corresponds to on-axis minority fundamental cyclotron resonance of protons at 5.3 T and absorbing fast waves by hydrogen minority species in a deuterium plasma. It can be very efficient (typical single pass absorption in C-Mod is 80–90% for minority concentrations of 5–10%).
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There is a special High Limit Slots area, featuring slot machines with payouts up to $500,000. The race and sports book is a state of- the-art betting area that features thirty-six 60-inch plasma TVs, along with twenty-four 42-inch plasmas. Bets are offered on a range of sports including soccer, football, boxing, MMA and more. They are also the first room to offer what they call "SkyBoxes".
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The stellarator, various pinch concepts and the magnetic mirror machines in both the US and USSR all demonstrated problems that limited their confinement times. From the first studies of controlled fusion, there was a problem lurking in the background. During the Manhattan Project, David Bohm had been part of the team working on isotopic separation of uranium. In the post-war era he continued working with plasmas in magnetic fields.
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Argon compounds, the chemical compounds that contain the element argon, are rarely encountered due to the inertness of the argon atom. However, compounds of argon have been detected in inert gas matrix isolation, cold gases, and plasmas, and molecular ions containing argon have been made and also detected in space. One solid interstitial compound of argon, Ar1C60 is stable at room temperature. Ar1C60 was discovered by the CSIRO.
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As it is usually assumed in setting up coordinates for describing magnetically confined plasmas that the set r,\theta,\zeta forms a right-handed coordinate system, abla r\cdot abla\theta\times abla\zeta > 0, we must either reverse the poloidal direction by taking s_\theta = -1, s_\zeta = +1, or reverse the toroidal direction by taking s_\theta = +1, s_\zeta = -1. Both choices are used in the literature.
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It is nearly impossible to acquire satisfactory data for the properties of materials expected to be subject to an intense neutron flux, and burning plasmas are expected to have quite different properties from externally heated plasmas. Supporters contend that the answer to these questions requires the ITER experiment, especially in the light of the monumental potential benefits. Furthermore, the main line of research via tokamaks has been developed to the point that it is now possible to undertake the penultimate step in magnetic confinement plasma physics research with a self-sustained reaction. In the tokamak research program, recent advances devoted to controlling the configuration of the plasma have led to the achievement of substantially improved energy and pressure confinement, which reduces the projected cost of electricity from such reactors by a factor of two to a value only about 50% more than the projected cost of electricity from advanced light-water reactors.
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Since the creation of the Plasma Laboratory for Fusion Energy and Applications in 2011, coordinator Vargas-Blanco has promoted seventeen research projects in fusion, plasmas and their applications for Costa Rican medical, agricultural and industrial uses. These projects got the attention of the University of Wisconsin-Madison in the United States compelling them to donate a spherical tokamak, known as a MEDUSA (Madison Education Small Aspect Ratio, now known as MEDUSA-CR), to Tecnologico de Costa Rica, thus turning the university into one of the few in the world boasting both a Stellarator and a spherical tokamak. Thanks to his perseverance and leadership, Vargas-Blanco has consolidated his research group to be recognized within the international scientific community for innovations in plasmas and fusion applications and positioning Costa Rica as a reference in Latin America in this exciting new field of scientific endeavor. From 20–31 January 2014, Vargas-Blanco organized in Costa Rica three international Plasma Physics and Nuclear Fusion conferences and one Plasma Physics Workshop.
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Petviashvili was born in Tbilisi to a family of scientists in 1936. In 1959, he graduated from Tbilisi State University. After defending his doctoral dissertation in March 1979, Petviashvili expanded his research interests to nonlinear drift waves and drift turbulence, which were critical in the development of the theory of plasmas. Petviashvili showed that drift turbulence can have some regularities in its chaotic structure and consists of structural elements— two-dimensional soliton vortices.
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A phase is a form of matter that has a relatively uniform chemical composition and physical properties (such as density, specific heat, refractive index, and so forth). These phases include the three familiar ones (solids, liquids, and gases), as well as more exotic states of matter (such as plasmas, superfluids, supersolids, Bose–Einstein condensates, ...). A fluid may be a liquid, gas or plasma. There are also paramagnetic and ferromagnetic phases of magnetic materials.
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They are also used in microwave linear beam vacuum tubes such as klystrons, inductive output tubes, travelling wave tubes, and gyrotrons, as well as in scientific instruments such as electron microscopes and particle accelerators. Electron guns may be classified by the type of electric field generation (DC or RF), by emission mechanism (thermionic, photocathode, cold emission, plasmas source), by focusing (pure electrostatic or with magnetic fields), or by the number of electrodes.
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A simplified Paschen Breakdown Curve for most gases There are 4 states of matter: solid, liquid, gas, and plasma. Plasmas make up more than 99% of the visible universe. In general, when energy is applied to a gas, internal electrons of gas molecules (atoms) are excited and move up to higher energy levels. If the energy applied is high enough, outermost electron(s) can even be stripped off the molecules (atoms), forming ions.
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VSim is used for modeling basic electromagnetics and plasma physics, complex metallic and dielectric shapes, photonics, vacuum electronics including multipactor effects, laser wake-field acceleration, plasma thrusters, and fusion plasmas. The Vorpal computational engine is highly flexible. It is arbitrary dimensional, meaning that it can be run in one, two, or three dimensions. It can be run in full electromagnetic mode, using the FDTD algorithm, or with electrostatically or magnetostatically computed fields.
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Magnetically confined fusion plasmas such as those generated in tokamaks and stellarators are characterized by a typical shape. Plasma shaping is the study of the plasma shape in such devices, and is particularly important for next step fusion devices such as ITER. This shape is conditioning partly the performance of the plasma. Tokamaks, in particular, are axisymmetric devices, and therefore one can completely define the shape of the plasma by its cross- section.
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The main calutron patents were Methods of and apparatus for separating materials (Lawrence), Magnetic shims (Oppenheimer and Frankel), and Calutron system (Lawrence). Burhop and Bohm later studied the characteristics of electric discharges in magnetic fields, today known as Bohm diffusion. Their papers on the properties of plasmas under magnetic containment would find usage in the post-war world in research into controlled nuclear fusion. Other technical problems were more mundane but no less important.
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This branch of spectroscopy deals with radiation related to atoms that are stripped of several electrons (multiply ionized atoms (MIA), multiply charged ions, highly charged ions). These are observed in very hot plasmas (laboratory or astrophysical) or in accelerator experiments (beam-foil, electron beam ion trap (EBIT)). The lowest exited electron shells of such ions decay into stable ground states producing photons in VUV, EUV and soft X-ray spectral regions (so-called resonance transitions).
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Through the 1960s ZETA was not the only experiment to suffer from unexpected performance problems. Problems with plasma diffusion across the magnetic fields plagued both the magnetic mirror and stellarator programs, at rates that classical theory could not explain. Adding more fields did not appear to correct the problems in any of the existing designs. Work slowed dramatically as teams around the world tried to better understand the physics of the plasmas in their devices.
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In 1985, Matthaeus received the James B. MacElwane Award from the American Geophysical Union and became its fellow. He was then elected a fellow of the American Physical Society in 1998. In 2019, he received the James Clerk Maxwell Prize for Plasma Physics for "pioneering research into the nature of turbulence in space and astrophysical plasmas, which has led to major advances in understanding particle transport, dissipation of turbulent energy, and magnetic reconnection".
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However, once the width exceeds this distance, then the collection increasingly deviates from this theory. If the tether geometry is a flat tape, then an approximation can be used to convert the normalized tape width to an equivalent cylinder radius. This was first done by Sanmartin and EstesSanmartin, J.R., and Estes, R.D., "The orbital-motion- limited regime of cylindrical Langmuir probes," Physics of Plasmas, Vol. 6, No. 1, 1999, pp. 395–405.
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The first layer is a positive layer at the edge of the high potential plasma (the contactor plasma cloud). The second layer is a negative layer at the edge of the low potential plasma (the ambient plasma). Further investigation of the double layer phenomenon has been conducted by several people.Lapuerta, V., and Ahedo, E., " Dynamic model of a plasma structure with an intermediate double-layer, formed outside an anodic plasma contactor," Physics of Plasmas, Vol.
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These observational results complement computer simulations of star-formation, which also emphasize the role that molecular-cloud filaments play in the birth of stars. Observations by the space-based Chandra X-ray Observatory have shown a diffuse X-ray glow from the H II region, which is likely due to the presence of a multi-million Kelvin plasma. Such hot plasmas can be produced by winds from massive stars, which become shock heated.
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Plasmas are by far the most common phase of ordinary matter in the universe, both by mass and by volume.It is assumed that more than 99% the visible universe is made of some form of plasma. . Above the Earth's surface, the ionosphere is a plasma, and the magnetosphere contains plasma. Within our Solar System, interplanetary space is filled with the plasma expelled via the solar wind, extending from the Sun's surface out to the heliopause.
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The other, known as the particle-in-cell (PIC) technique, includes kinetic information by following the trajectories of a large number of individual particles. Kinetic models are generally more computationally intensive than fluid models. The Vlasov equation may be used to describe the dynamics of a system of charged particles interacting with an electromagnetic field. In magnetized plasmas, a gyrokinetic approach can substantially reduce the computational expense of a fully kinetic simulation.
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Stephen Bernard Libby from the Lawrence Livermore National Laboratory. He was awarded the status of Fellow in the American Physical Society, after he was nominated by their American Physical Society in 1999, for the application of quantum field theory to diverse systems including perturbative quantum chromodynamics and transport in the quantum Hall effect, as well as inventing computational algorithms for radiation driven kinetics in plasmas, and the invention of novel short wavelength laser applications.
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James Douglas Beason, from the Air Force Research Laboratory, was awarded the status of Fellow of the American Physical Society after being nominated by the APS in 2000. The honor was for his advancement of national science policy, especially for his impact throughout the government on basic research. In addition, he has fundamentally advanced science in his work toward solving the relativistic Compton scattering kernel, and inventing innovative techniques for simulating lasers and plasmas.
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William Arthur Coles, from the University of California, San Diego, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Topical Group in Plasma Astrophysics in 2006, for his major contributions to our understanding of the effect of plasma turbulence on radio wave propagation, and the use of radio propagation measurements to infer properties of remote turbulent plasmas in interplanetary space and the interstellar medium.
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Betsy Ancker-Johnson (born April 29, 1927 died July 2nd 2020) is an American plasma physicist. She is known for her research into instabilities that can occur in plasmas in solids, and for her invention of a gigacycle range signal generator using semiconductor materials in magnetic and electric fields. She was the first woman Presidential appointee in the U.S. Department of Commerce. She is the fourth woman elected to the National Academy of Engineering.
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In 1983 he received the "Prix Gegner of the Académie des Sciences, Paris," in 1987 the "Prix du CEA," and in 2001 the American Physical Society's Tom W. Bonner Prize in Nuclear Physics, shared with Claude Lyneis. A prize awarded by Pantechnik (a manufacturer of ECR sources) is named after him and is delivered every 2 year at the ECRIS international conference. He authored a book Electron Cyclotron Resonance Ion Sources and ECR Plasmas.
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Lawson's analysis is based on the rate of fusion and loss of energy in a thermalized plasma. There is a class of fusion machines that do not use thermalized plasmas but instead directly accelerate individual ions to the required energies. The best-known examples are the migma, fusor and polywell. When applied to the fusor, Lawson's analysis is used as an argument that conduction and radiation losses are the key impediments to reaching net power.
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Annual Review of Fluid Mechanics is a peer-reviewed scientific journal covering research on fluid mechanics. It is published once a year by Annual Reviews and the editors-in-chief are Parviz Moin and Howard Stone. According to the Journal Citation Reports, the journal has a 2019 impact factor of 16.306, ranking it first out of 136 journals in the category "Mechanics" and first out of 34 journals in "Physics, Fluids and Plasmas".
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Plasmas and their embedded magnetic fields affect the formation, evolution and destiny of planets and planetary systems. The heliosphere shields the solar system from galactic cosmic radiation. Our habitable planet is shielded by its magnetic field, protecting it from solar and cosmic particle radiation and from erosion of the atmosphere by the solar wind. Planets without a shielding magnetic field, such as Mars and Venus, are exposed to those processes and evolve differently.
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He believed early on that damage to the skin was not caused by the Roentgen rays, but by the ozone generated in contact with the skin, and to a lesser extent, by nitrous acid. Tesla incorrectly believed that X-rays were longitudinal waves, such as those produced in waves in plasmas. These plasma waves can occur in force-free magnetic fields.Griffiths, David J. Introduction to Electrodynamics, and Jackson, John D. Classical Electrodynamics, .
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From 1958 through 1988, the journal included plasma physics. From 1989 until 1993, the journal split into Physics of Fluids A covering fluid dynamics, and Physics of Fluids B, on plasma physics. In 1994, the latter was renamed Physics of Plasmas, and the former continued under its original name, Physics of Fluids. The journal was originally published by the American Institute of Physics in cooperation with the American Physical Society's Division of Fluid Dynamics.
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Properties of the piezoelectric direct discharge plasmas enable a large spectrum of applications in medical technology, microbiology and clinical research.A. Fridman, G. Friedman, "Plasma Medicine", Wiley; 1 edition (February 11, 2013) Typical industrial applications include ultra-fine cleaning and plasma activation of metal, ceramic, glass and plastic surfaces. Such plasma processing increases the surface energy improving the surface wettability and adhesion. The latter increases the quality of the subsequent printing or gluing.
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GEM solves the electromagnetic gyrokinetic equations which are the appropriate equations for well magnetized plasmas. The plasma is treated statistically as a kinetic distribution function. The distribution function depends on the three-dimensional position, the energy and magnetic moment. The time evolution of the distribution function is described by gyrokinetic theory which simply averages the Vlasov-Maxwell system of equations over the fast gyromotion associated with particles exhibiting cyclotron motion about the magnetic field lines.
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244 (1977) his discovery, independently of Roland Svensson of Sweden, of the negative heat behavior of optically thin, hot thermal plasmas dominated by electron-positron pairs, that is, the result that adding energy to thin hot gases causes their temperature to decrease rather than increase;Astrophysical Journal, vol. 253, pg. 842 (1982) and his work on unusual radiation processes, such as unsaturated inverse Compton scattering, in thermal media, also with wide application in astrophysics.Nature, vol.
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In the pioneering experiment, Los Alamos National Laboratory's FRX-L,FRX-L: A Plasma Injector for Magnetized Target Fusion a plasma is first created at low density by transformer-coupling an electric current through a gas inside a quartz tube (generally a non-fuel gas for testing purposes). This heats the plasma to about (~2.3 million degrees). External magnets confine fuel within the tube. Plasmas are electrically conducting, allowing a current to pass through them.
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Carbon Sports Bar opened in December 2007 and features a giant 12.5 x 4m wide screen and 16 x 52-inch plasmas. In December 2008, Burswood opened its new world-class dedicated poker room featuring plasma screens, dedicated bar and lounge area. In November 2009, Britney Spears performed 2 shows at the arena for her highly anticipated The Circus Starring Britney Spears tour. The shows at Burswood were Spears' first concerts in Australia.
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Sir Steven Charles Cowley (born 1959) is a British theoretical physicist and international authority on nuclear fusion and astrophysical plasmas. He has served as director of the United States Department of Energy (DOE) Princeton Plasma Physics Laboratory (PPPL) since 1 July 2018. Previously he served as president of Corpus Christi College, Oxford, since October 2016. and head of the EURATOM / CCFE Fusion Association and chief executive officer of the United Kingdom Atomic Energy Authority (UKAEA).
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This would remove the ions before they drifted too far and hit the walls. It would also remove any heavier elements in the plasma. Using classical calculations the rate of diffusion through collisions was low enough that it would be much lower than the drift due to uneven fields in a normal toroid. But earlier studies of magnetically confined plasmas in 1949 demonstrated much higher losses and became known as Bohm diffusion.
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The polywell biggest flaw is its ability to hold a plasma negative for any significant amount of time. In practice, any significant amount of negative charge vanishes quickly. Additionally, analysis by Todd Rider in 1995 suggests that any system that has non-equilibrium plasmas will suffer from rapid losses of energy due to bremsstrahlung. Bremsstrahlung occurs when a charged particle is rapidly accelerated, causing it to radiate x-rays, and thereby lose energy.
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The Debye–Hückel theory was proposed by Peter Debye and Erich Hückel as a theoretical explanation for departures from ideality in solutions of electrolytes and plasmas. It is a linearized Poisson–Boltzmann model, which assumes an extremely simplified model of electrolyte solution but nevertheless gave accurate predictions of mean activity coefficients for ions in dilute solution. The Debye–Hückel equation provides a starting point for modern treatments of non-ideality of electrolyte solutions.
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NASA to generate neutrons from D-D reactions. The simplest and most direct method proved to be in a predetonated stoichiometric mixture of deuterium-oxygen. The other successful method was using a miniature Voitenko compressor,D.Sagie and I.I. Glass (1982) "Explosive-driven hemispherical implosions for generating fusion plasmas" where a plane diaphragm was driven by the implosion wave into a secondary small spherical cavity that contained pure deuterium gas at one atmosphere.
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Since the distance between the Zeeman sub- levels is a function of the magnetic field, this effect can be used to measure the magnetic field, e.g. that of the Sun and other stars or in laboratory plasmas. The Zeeman effect is very important in applications such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance imaging (MRI) and Mössbauer spectroscopy. It may also be utilized to improve accuracy in atomic absorption spectroscopy.
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Charged particle beams in a particle accelerator or a storage ring undergo a variety of different processes. Typically the beam dynamics is broken down into single particle dynamics and collective effects. Sources of collective effects include single or multiple inter-particle scattering and interaction with the vacuum chamber and other surroundings, formalized in terms of impedance. The collective effects of charged particle beams in particle accelerators share some similarity to the dynamics of plasmas.
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The size of the arrows corresponds to the magnitude of the flow velocity. A sawtooth is a relaxation that is commonly observed in the core of tokamak plasmas, first reported in 1974. The relaxations occur quasi-periodically and cause a sudden drop in the temperature and density in the center of the plasma. A soft-xray pinhole camera pointed toward the plasma core during sawtooth activity will produce a sawtooth-like signal.
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A magnetohydrodynamic generator is an MHD converter that transforms the kinetic energy of an electrically conductive fluid, in motion with respect to a steady magnetic field, into electricity. MHD power generation has been tested extensively in the 1960s with liquid metals and plasmas as working fluids. Basically, a plasma is hurtling down within a channel whose walls are fitted with electrodes. Electromagnets create a uniform transverse magnetic field within the cavity of the channel.
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A ball at rest in a valley (right) will return to the bottom if moved slightly, or perturbed, and is thus dynamically stable. One on the top of a hill (left) will accelerate away from its rest point if perturbed, and is thus dynamically unstable. Plasmas have many mechanisms that make them fall into the second group under certain conditions. The stability of a plasma is an important consideration in the study of plasma physics.
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However, it is usually accompanied by physical or chemical changes that permanently degrade the material's insulating properties. Materials that lack electron conduction are insulators if they lack other mobile charges as well. For example, if a liquid or gas contains ions, then the ions can be made to flow as an electric current, and the material is a conductor. Electrolytes and plasmas contain ions and act as conductors whether or not electron flow is involved.
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ALPHA faces several challenges. Magnetic traps – wherein neutral atoms are trapped using their magnetic moments – are notoriously weak; only atoms with kinetic energies equivalent to less than one kelvin may be trapped. The cold antihydrogen created first in 2002 by the ATHENA and the ATRAP collaborations was produced by merging cold plasmas of positrons (also called antielectrons) and antiprotons. While this method has been quite successful, it creates antiatoms with kinetic energies too large to be trapped.
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A definition of "matter" based on its physical and chemical structure is: matter is made up of atoms. Such atomic matter is also sometimes termed ordinary matter. As an example, deoxyribonucleic acid molecules (DNA) are matter under this definition because they are made of atoms. This definition can be extended to include charged atoms and molecules, so as to include plasmas (gases of ions) and electrolytes (ionic solutions), which are not obviously included in the atoms definition.
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Ilya Prigogine) at the Service de Physique Théorique et Mathématique. He became a professor at the ULB in 1964. He worked on the statistical physics of charged particles (Bălescu-Lenard collision operator) and on the theory of transport of magnetically confined plasmas. Radu Balescu was involved in the European fusion programme for more than 30 years as a scientist and as the head of research unit of the ULB group in the Euratom- Belgian state Association.
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It was first observed in 1949 by David Bohm, E. H. S. Burhop, and Harrie Massey while studying magnetic arcs for use in isotope separation.Bohm, D. (1949) The characteristics of electrical discharges in magnetic fields, A. Guthrie and R. K. Wakerling (eds.), New York: McGraw-Hill. It has since been observed that many other plasmas follow this law. Fortunately there are exceptions where the diffusion rate is lower, otherwise there would be no hope of achieving practical fusion energy.
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A surface-wave-sustained discharge is a plasma that is excited by propagation of electromagnetic surface waves. Surface wave plasma sources can be divided into two groups depending upon whether the plasma generates part of its own waveguide by ionisation or not. The former is called a self-guided plasma. The surface wave mode allows the generation of uniform high-frequency-excited plasmas in volumes whose lateral dimensions extend over several wavelengths of the electromagnetic wave, e.g.
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The non-vanishing penetration depth of an evanescent wave opens an alternative way of heating a plasma: Instead of traversing the plasma, the conductivity of the plasma enables the wave to propagate along the plasma surface. The wave energy is then transferred to the plasma by an evanescent wave which enters the plasma perpendicular to its surface and decays exponentially with the skin depth. Transfer mechanism allows to generate over-dense plasmas with electron densities beyond the critical density.
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This has important implications for magnetic dynamos. In fact, a very high electrical conductivity translates into high magnetic Reynolds numbers, which indicates that the plasma will be turbulent. In fact, the conventional views on flux freezing in highly conducting plasmas are inconsistent with the phenomenon of spontaneous stochasticity. It has become a standard argument even in textbooks, unfortunately, that magnetic flux freezing should hold better and better as magnetic diffusivity tends to zero (non-dissipative regime).
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Friedwardt Winterberg (born June 12, 1929) is a German-American theoretical physicist and research professor at the University of Nevada, Reno. He is known for his research in areas spanning general relativity, Planck scale physics, nuclear fusion, and plasmas. His work in nuclear rocket propulsion earned him the 1979 Hermann Oberth Gold Medal of the Wernher von Braun International Space Flight FoundationAstronautics & Aeronautics Magazine, AIAA, v. 17, p 83, 1979, Bio from the University of Nevada, Reno website.
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Cross section of the SSPX vacuum vessel The Sustained Spheromak Physics Experiment (SSPX) is a program at Lawrence Livermore National Laboratory in the United States established to investigate spheromak plasma.Sustained Spheromak Physics Experiment - SSPX MFEScience. 2008-03-27. A spheromak device produces a plasma in magnetohydrodynamic equilibrium mainly through self- induced plasma currents, as opposed to a tokamak device which depends on large externally generated magnetic fields.Experiment mimics nature's way with plasmas LLNL. 2008-03-27.
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Phosphorus oxide in high concentrations interacts with ambient moisture to produce phosphoric acid. Crystals of BPO4 can also precipitate from the flowing glass on cooling; these crystals are not readily etched in the standard reactive plasmas used to pattern oxides, and will result in circuit defects in integrated circuit manufacturing. Besides these intentional impurities, CVD oxide may contain byproducts of the deposition. TEOS produces a relatively pure oxide, whereas silane introduces hydrogen impurities, and dichlorosilane introduces chlorine.
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The Magnetospheric Multiscale (MMS) Mission is a NASA robotic space mission to study the Earth's magnetosphere, using four identical spacecraft flying in a tetrahedral formation. The spacecraft were launched on 13 March 2015 at 02:44 UTC. The mission is designed to gather information about the microphysics of magnetic reconnection, energetic particle acceleration, and turbulence—processes that occur in many astrophysical plasmas. As of March 2020, the MMS spacecraft have enough fuel to remain operational until 2040.
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Another phase commonly encountered in the study of chemistry is the aqueous phase, which is the state of substances dissolved in aqueous solution (that is, in water). Less familiar phases include plasmas, Bose–Einstein condensates and fermionic condensates and the paramagnetic and ferromagnetic phases of magnetic materials. While most familiar phases deal with three-dimensional systems, it is also possible to define analogs in two-dimensional systems, which has received attention for its relevance to systems in biology.
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The heliosphere's structure is due to the invisible interaction between the solar wind and cold gas from the local interstellar medium. The creation of ENAs by space plasmas was predicted but their discovery was both deliberate and serendipitous. While some early efforts were made at detection, their signatures also explained inconsistent findings by ion detectors in regions of expected low ion populations. Ion detectors were co-opted for further ENA detection experiments in other low-ion regions.
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A Coulomb collision is a binary elastic collision between two charged particles interacting through their own electric field. As with any inverse- square law, the resulting trajectories of the colliding particles is a hyperbolic Keplerian orbit. This type of collision is common in plasmas where the typical kinetic energy of the particles is too large to produce a significant deviation from the initial trajectories of the colliding particles, and the cumulative effect of many collisions is considered instead.
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In 1963, he received the degree of civilingenjör from the Royal Institute of Technology, Stockholm, in 1970 the Tekn. lic., and in 1980 the Tekn. D. He is currently affiliated with the Royal Institute of Technology, Stockholm, at the School of Electrical Engineering in the department of Space & Plasma Physics.Web page of Per Calqvist He is the author of several papers on astrophysical plasmas, from the formation of stars, double layers, the Bennett Pinch, to interstellar helical filaments.
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This journal began as "Physical Review" in 1893. In 1913 the American Physical Society took over "Physical Review". In 1970 "Physical Review" was subdivided into Physical Review A, B, C, and D. From 1990 until 1993 a process was underway which split the journal then entitled " Physical Review A: General Physics" into two journals. Hence, from 1993 until 2000, one of the split off journals became Physical Review E: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics.
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Ernst Willi Messerschmid (born 21 May 1945) is a German physicist and former astronaut. Born in Reutlingen, Germany, Messerschmid finished the Technisches Gymnasium in Stuttgart in 1965. After two years of military service he studied physics at the University of Tübingen and Bonn, receiving a Diplom degree in 1972 and doctorate in 1976. From 1970 to 1975 he was also a visiting scientist at the CERN in Geneva, working on proton beams in accelerators and plasmas.
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Work Featured in the National Science Foundation Visualization Challenge 2012 Interactive Plasmas James Falk (born May 1, 1954) is a research scientist, conceptual engineer, technological artist, inventor and U.S Patent consultant. His invention of the Groundstar style of Plasma globe was commercialized and marketed to collectors and science museums in the 1970s and 1980s. His techno- art was marketed through major retail catalog chains & stores such as The Sharper Image. In 2001 he became CEO of EFX,Inc.
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The photoelectric effect will cause spacecraft exposed to sunlight to develop a positive charge. This can be a major problem, as other parts of the spacecraft are in shadow which will result in the spacecraft developing a negative charge from nearby plasmas. The imbalance can discharge through delicate electrical components. The static charge created by the photoelectric effect is self-limiting, because a higher charged object doesn't give up its electrons as easily as a lower charged object does.
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Polywells are improvements on this design, designed to reduce conduction losses by removing the wire cages which cause them."The Advent of Clean Nuclear Fusion: Super-performance Space Power and Propulsion", Robert W. Bussard, Ph.D., 57th International Astronautical Congress, October 2–6, 2006 Regardless, it is argued that radiation is still a major impediment.odd H. Rider, "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium" Physics of Plasmas, April 1997, Volume 4, Issue 4, pp. 1039–1046.
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ASCA was the first X-ray astronomy mission to combine imaging capability with a broad pass band, good spectral resolution, and a large effective area. The mission also was the first satellite to use CCDs for X-ray astronomy. With these properties, the primary scientific purpose of ASCA is the X-ray spectroscopy of astrophysical plasmas, especially the analysis of discrete features such as emission lines and absorption edges. ASCA carried four large-area X-ray telescopes.
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They discovered the Kinetic Alfvén wave, which resolves the logarithmic singularity of magnetohydrodynamic shear Alfvén waves and plays important roles in the heating, acceleration and transport of charged particles in solar, magnetospheric, and laboratory plasmas. Before joining the faculty at UCI, Chen was a professor at the Princeton University. Chen was the Deputy Head of the Theory Division of the Princeton Plasma Physics Laboratory. From 1993 till 2012, Chen was a professor of physics at UCI.
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A Q-machine is a device that is used in experimental plasma physics. The name Q-machine stems from the original intention of creating a quiescent plasma that is free from the fluctuations that are present in plasmas created in electric discharges. The Q-machine was first described in a publication by Rynn and D'Angelo . The Q-machine plasma is created at a plate that has been heated to about 2000 K and hence is called the hot plate.
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Viachelav V. Belyi, also referred to as Slava Belyi (1 August 1945 – 20 May 2020) was a Russian scientist, specialised in physics-thermodynamics, Laureate of a scientist Prize of the Russian Federation (1991, together with Irina Veretennikoff and Yuri Klimontovich), junior, then senior and finally chief scientist at IZMIRAN (1971–2020), collaborator of Nobel prize Laureate Ilya Prigogine in 1980s and 1990s with an external affiliation to the Laboratoire de physique des plasmas at the ULB (Brussels, Belgium).
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Winston H. Bostick (March 5, 1916 – January 19, 1991) was an American physicist who discovered plasmoids, plasma focus, and plasma vortex phenomena. He simulated cosmical astrophysics with laboratory plasma experiments, and showed that Hubble expansion can be produced with repulsive mutual induction between neighboring galaxies acting as homopolar generators. His work on plasmas was claimed to be evidence for finite-sized elementary particles and the composition of strings, but this is not accepted by mainstream science.
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During its operation, the experimental team noticed that on occasion the plasma would maintain confinement long after the experimental run had ostensibly ended, although this was not then studied in depth. Years later in 1974, John Bryan Taylor characterized these self-stable plasmas, which he called "quiescent". He developed the Taylor state equilibrium concept, a plasma state that conserves helicity in its lowest possible energy state. This led to a re-awakening of compact toroid research.
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The Rotating wall technique (or RW technique) is a method used to compress a single-component plasma (a cold dense gas of charged particles) confined in an electromagnetic trap. It is one of many scientific and technological applications that rely on storing charged particles in vacuum. This technique has found extensive use in improving the quality of these traps and in tailoring of both positron and antiproton (i.e. antiparticle) plasmas for a variety of end uses.
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She has her bachelor's degree in physics, chemistry, and applied maths from Rhodes University in 1976 and an honours in Physics, 1977. She earned her PhD in plasma physics in 1983 from the University of Natal. Her research topic was Ion Acoustic Waves in Multi- Species Plasmas. She did postdocs at the University of California, Los Angeles in thermonuclear fusion, and in Space Shuttle-related plasma simulation at Stanford University's Space, Telecommunications and Radioscience Lab (STARLab).
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The background plasma slowed the confined fast ions, in a similar way to how air resistance slows down a baseball. The energy transfer from the fast ions to the plasma increased the overall plasma temperature. The neutral beam injector used in START was on loan from Oak Ridge National Laboratory. Sykes, Alan, and R.J. La Haye. "High Beta Produced By Neutral Beam Injection In The START (Small Tight Aspect Ratio Tokamak).." Physics Of Plasmas 4.5 (1997): 1665.
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After receiving his Ph.D. in 1977, Goldston was offered a staff position at the Princeton Plasma Physics Laboratory. His early work there involved studying how plasmas are heated by energetic ions, with the ultimate goal being the construction of a fusion reactor, a device that would generate fusion reactions of light nuclei rather than fission reactions of heavy nuclei. In a 1979 interview, Goldston explained the significance of his research: "If we can accomplish this, we will have created an inexhaustible fuel, which will burn without leaving the quantities of dangerous radioactive waste generated by the atomic power plants we have now." Later that decade, Goldston produced physical evidence that fast ions circulating in toroidal magnetically confined plasmas such as the tokamak configuration slowed down in good agreement with classical collision theory, thus providing a physical underpinning for the further development of the powerful neutral beam systems which have heated and driven electric current in successive generations of tokamaks and other magnetic plasma confinement devices such as stellarators.
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Microplasma can contact skin without harming it, making it ideal for disinfecting wounds. “Medical plasmas are said to be in the ‘Goldilocks’ range—hot enough to produce and be an effective treatment, but cold enough to leave tissues unharmed” (Larousi, Kong 1). Researchers have found that microplasmas can be applied directly to living tissues to deactivate pathogens. Scientists have also discovered that microplasmas stop bleeding without damaging healthy tissue, disinfect wounds, accelerate wound healing, and selectively kill some types of cancer cells.
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The journal covers research on atomic, molecular physics and optical physics which is known by researchers in the field as "AMO physics". Topics include atomic and molecular structure, spectra and collisions, ultracold matter, quantum optics and non linear optics, quantum information, laser physics, intense laser fields, ultrafast and x-ray physics and atomic and molecular physics in plasmas. The journal publishes research papers, Fast Track Communications (FTCs), topical reviews, tutorials and invited articles. It publishes Special Issues on developing research fields.
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Bell was awarded the 2014 Fred Hoyle Medal and Prize of the Institute of Physics "for elucidating the origin and impact of cosmic rays and for his seminal contributions to electron energy transport in laboratory plasmas". In 2016 he was awarded the Eddington Medal of the Royal Astronomical Society for "his development of the theory of the acceleration of charged particles in astrophysics, known as Diffusive Shock Acceleration". He was elected a Fellow of the Royal Society (FRS) in 2017.
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Friedrich E. Wagner (born November 16, 1943, sometimes abbreviated as Fritz Wagner) is a German physicist and emeritus professor who specializes in plasma physics. He was known to have discovered the high-confinement mode (i.e. H-mode) of magnetic confinement in fusion plasmas while working at the ASDEX tokamak in 1982. For this discovery and his subsequent contributions to fusion research, was awarded the John Dawson Award in 1987, the Hannes Alfvén Prize in 2007 and the Stern–Gerlach Medal in 2009.
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Dissociative recombination is a process where a positive molecular ion recombines with an electron, and as a result, the neutral molecule dissociates. This reaction is important for extraterrestrial and atmospheric chemistry. On Earth, dissociative recombination rarely occurs naturally, as free electrons react with any molecule (even neutral molecules) they encounter. Even in the best laboratory conditions, dissociative recombination is hard to observe, but is an important reaction in systems that have large populations of ionized molecules, for instance in atmospheric-pressure plasmas.
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From 1995, the former distributors of Fusion, Jenton / Jenact, expanded on the fact that energised UV-emitting plasmas act as lossy conductors to create a number of patents regarding electrodeless UV lamps for sterilising and germicidal uses. Around 2000, a system was developed that concentrated radio frequency waves into a solid dielectric waveguide made of ceramic which energized a light-emitting plasma in a bulb positioned inside. This system, for the first time, permitted an extremely bright and compact electrodeless lamp.
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LULI2000 is a high-power laser system dedicated to scientific research. It is located in LULI laboratory,Luli web page at École PolytechniqueÉcole Polytechnique in France. The main application of this type of laser is related to the very high energy fluxes obtained after focusing onto tiny focal spots, from micrometers to hundreds of micrometers in diameter. The interaction between these focused beams and small targets produces very hot plasmas, up to many hundred million degrees, high densities and high pressures.
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These beams are then focussed in the middle of a 2 m diameter vacuum chamber where they irradiate targets of different types. The interaction itself and the characteristics of the laser-generated hot plasmas are diagnosed by a whole set of dedicated diagnostics. PICO2000, the adaptation of one NANO2000 laser chain in the picosecond regime, will deliver 200 J in 1 ps at 1.05 μm. LULI2000 will be the most energetic laser facility in Europe coupling nanosecond and picosecond pulses.
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There is at present, no closed-form solution to account for the effects of plasma flow relative to the bare tether. However, numerical simulation has been recently developed by Choiniere et al. using KiPS-2D which can simulate flowing cases for simple geometries at high bias potentials.Choiniere, E., Gilchrist, B.E., Bilen, S.G., "Measurement of Cross-Section GeometryEffects on Electron Collection to Long Probes in Mesosonic Flowing Plasmas," 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, AIAA, 2003, pp. 1–13.
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Plasma and ionized gases have properties and behaviours unlike those of the other states, and the transition between them is mostly a matter of nomenclature and subject to interpretation. Based on the temperature and density of the environment that contains a plasma, partially ionized or fully ionized forms of plasma may be produced. Neon signs and lightning are examples of partially ionized plasmas. The Earth's ionosphere is a plasma and the magnetosphere contains plasma in the Earth's surrounding space environment.
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Pixel is a webcomic written by Chris Dlugosz, first published on June 14, 2002. It is set in the aptly named "pixel universe", inhabited by pixels, voxels, vectors, plasmas (a satire on the plasma screens used by Apple computers), and polygons. The comic is known for its very literal sense of humor, and its constant breaks of the fourth wall. The text of the comic is written entirely in upper case with very little punctuation other than the occasional hyphen or exclamation point.
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Magnetic anisotropy, for example, may occur in a plasma, so that its magnetic field is oriented in a preferred direction. Plasmas may also show "filamentation" (such as that seen in lightning or a plasma globe) that is directional. An anisotropic liquid has the fluidity of a normal liquid, but has an average structural order relative to each other along the molecular axis, unlike water or chloroform, which contain no structural ordering of the molecules. Liquid crystals are examples of anisotropic liquids.
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In the 1980s, Coppi was a member of the science team in the Voyager 2 space probe. Coppi works on theoretical plasma physics, space plasmas and magnetic fusion. At MIT, he initiated the Alcator Program, which led to the Russian-American Ignitor program, that aims at building near Moscow a fusion reactor with Coppi as the principal investigator for the project.MIT News 2010 on the Ignitor Program In addition, Coppi is taking a leading role in the Frascati Torus Program in Italy.
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Designs have been proposed to avoid the problems associated with the cage, by generating the field using a non-neutral cloud. These include a plasma oscillating device,"Stable, thermal equilibrium, large-amplitude, spherical plasma oscillations in electrostatic confinement devices", DC Barnes and Rick Nebel, PHYSICS OF PLASMAS VOLUME 5, NUMBER 7 JULY 1998 a magnetically-shielded-grid, a penning trap, the polywell, and the F1 cathode driver concept. The technology is relatively immature, however, and many scientific and engineering questions remain.
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Non-neutral plasmas with a single sign of charge can be confined for long periods of time using only static electric and magnetic fields. One such configuration is called a Penning trap, after the inventor F. M. Penning. The cylindrical version of the trap is also sometimes referred to as a Penning- Malmberg trap, after Prof. John Malmberg. The trap consists of several cylindrically symmetric electrodes and a uniform magnetic field applied along the axis of the trap (Fig 1).
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The analysis of line intensity ratios is an important tool to obtain information about laboratory and space plasmas. In emission spectroscopy, the intensity of spectral lines can provide various information about the plasma (or gas) condition. It might be used to determine the temperature or density of the plasma. Since the measurement of an absolute intensity in an experiment can be challenging, the ratio of different spectral line intensities can be used to achieve information about the plasma, as well.
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Vassilis Angelopoulos (; born February 13, 1965) is a Greek American physicist. He is a specialist on Space and Astrophysical Plasmas. Since July, 2007, he has been on the faculty of the Department of Earth, Planetary, and Space Sciences and the Institute of Geophysics and Planetary Physics at the University of California, Los Angeles (UCLA). Vassilis is currently the Principal Investigator of the ELFIN Cubesat mission and Co-Investigator of ELFIN-L, leading the energetic particle detector (EPD) experiment at UCLA.
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Rose served as captain in the Canadian artillery from 1942-1947. He worked at Bell Laboratories until joining the MIT Nuclear Engineering faculty in 1958. He led the development of the Department’s program in plasmas and controlled fusion, and was on the MIT faculty for the rest of his professional career. From 1969 to 1971, during a two year leave of absence, he worked at Oak Ridge National Laboratory, where he was the first director of their office of Long-range planning.
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Ion Flow and Fusion Reactivity, Characterization of a Spherically convergent ion Focus. PhD Thesis, Dr. Timothy A Thorson, Wisconsin-Madison 1996. Designs have been proposed to avoid the problems associated with the cage, by generating the field using a non-neutral cloud. These include a plasma oscillating device,"Stable, thermal equilibrium, large-amplitude, spherical plasma oscillations in electrostatic confinement devices", DC Barnes and Rick Nebel, PHYSICS OF PLASMAS VOLUME 5, NUMBER 7 JULY 1998 a penning trap and the polywell.
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In ferromagnetic substances like iron and in plasmas, magnetic forces can be understood by imagining that the field lines exert a tension, (like a rubber band) along their length, and a pressure perpendicular to their length on neighboring field lines. "Unlike" poles of magnets attract because they are linked by many field lines; "like" poles repel because their field lines do not meet, but run parallel, pushing on each other. The rigorous form of this concept is the electromagnetic stress–energy tensor.
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The classical-map hypernetted-chain method (CHNC method) is a method used in many-body theoretical physics for interacting uniform electron liquids in two and three dimensions, and for non-ideal plasmas. The method extends the famous hypernetted-chain method (HNC) introduced by J. M. J van Leeuwen et al. to quantum fluids as well. The classical HNC, together with the Percus–Yevick approximation, are the two pillars which bear the brunt of most calculations in the theory of interacting classical fluids.
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In order to successfully heat experiments in a spherical tokamak, physicists performed neutral beam injection. This involved interjecting hydrogen into hydrogen or deuterium plasmas, providing effective heating of both ions and electrons. Although the atoms were injected with no net electrostatic charge, as the beam passed through the plasma, the atoms were ionized as they bounced off the ions already in the plasma. Consequently, because the magnetic field inside the torus was circular, these fast ions were confined to the background plasma.
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The Wesson model offers an explanation fast sawtooth crashes in hot tokamaks. Wesson's model describes a sawtooth relaxation based on the non-linear evolution of the quasi-interchange (QI) mode. The nonlinear evolution of the QI does not involve much reconnection, so it does not have Sweet-Parker scaling and the crash can proceed much faster in high temperature, low resistivity plasmas given a resistive MHD model. However more accurate experimental methods for measuring q profiles in tokamaks were developed later.
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The Columbia Non-neutral Torus (CNT) is a small stellarator at the Columbia University Plasma Physics Laboratory designed by Thomas Sunn Pedersen with the aid of Wayne Reiersen and Fred Dahlgren of the Princeton Plasma Physics Laboratory to conduct the first investigation of non-neutral plasmas confined on magnetic surfaces. The experiment, which began operation in November 2004, is funded by the National Science Foundation and the United States Department of Energy in the form of a Faculty Early Career Development (CAREER) award.
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The mystery of why the US's simple mirrors were not seeing this problem was discovered at a meeting in 1961. Lev Artsimovich inquired how the US team had concluded they had stable plasmas lasting on the order of milliseconds. This turned out to be due to the readings of one diagnostic instrument. When Artsimovich learned they had not accounted for the measurement delay in these instruments, it became clear the US mirrors had been suffering from this problem all along.
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In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, or external force. Fluids are a phase of matter and include liquids, gases and plasmas. They are substances with zero shear modulus, or, in simpler terms, substances which cannot resist any shear force applied to them. Although the term "fluid" includes both the liquid and gas phases, in common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present.
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Of particular importance were the concepts of elongation and triangularity, referring to the cross-sectional shape of the plasma. Early tokamaks had all used circular cross-sections simply because that was the easiest to model and build, but over time it became clear that C or (more commonly) D-shaped plasma cross-sections led to higher performance. This produces plasmas with high "shear", which distributed and broke up turbulent eddies in the plasma. These changes led to the "advanced tokamak" designs, which include ITER.
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A microplasma is a plasma of small dimensions, ranging from tens to thousands of micrometers. Microplasmas can be generated at a variety of temperatures and pressures, existing as either thermal or non-thermal plasmas. Non-thermal microplasmas that can maintain their state at standard temperatures and pressures are readily available and accessible to scientists as they can be easily sustained and manipulated under standard conditions. Therefore, they can be employed for commercial, industrial, and medical applications, giving rise to the evolving field of microplasmas.
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Gas particles are widely separated from one another, and consequently, have weaker intermolecular bonds than liquids or solids. These intermolecular forces result from electrostatic interactions between gas particles. Like-charged areas of different gas particles repel, while oppositely charged regions of different gas particles attract one another; gases that contain permanently charged ions are known as plasmas. Gaseous compounds with polar covalent bonds contain permanent charge imbalances and so experience relatively strong intermolecular forces, although the molecule while the compound's net charge remains neutral.
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49, 614 (2009)M. Teschke and J. Engemann, US020090122941A1, U.S. Patent application Since the piezoelectric material of the transformer, such as lead zirconate titanate, is often a dielectric, the produced electric discharge resembles properties of the dielectric barrier discharge. In addition, when operated in far from the electric ground, it also produces corona discharges on the sharp edges of the piezo-transformer. Due to the unique construction principles, the piezoelectric barrier discharge is the economic and compact source of the dielectric barrier and corona plasmas.
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Some of the atoms in the gas of a cell then lose electrons and become ionized, which creates an electrically conducting plasma of atoms, free electrons, and ions. The collisions of the flowing electrons in the plasma with the inert gas atoms leads to light emission; such light-emitting plasmas are known as glow discharges. Relative spectral power of red, green and blue phosphors of a common plasma display. The units of spectral power are simply raw sensor values (with a linear response at specific wavelengths).
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The Versatile Toroidal Facility (VTF) is a research group within the Physics Research Division of the MIT Plasma Science and Fusion Center at the Massachusetts Institute of Technology. The VTF is a laboratory focused on studying the phenomenon of magnetic reconnection. For this purpose the group has a small tokamak designed to observe rarefied plasmas with probes. These probes measure electric and magnetic field behavior as well as various plasma characteristics in order to better understand the poorly understood processes involved in magnetic reconnection.
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He played an important role in the study of the H-mode (i.e. high- confinement mode) discovered in 1982 at the ASDEX tokamak in magnetically enclosed fusion plasmas and the underlying transport mechanisms, in particular the suppression of turbulence by the formation of shear currents. Burrell was involved in the discovery of quiet H-mode (quiescent H-mode) at DIII-D in 1999, which has the advantages of H-modes but no edge instabilities (edge localized modes, ELM). Burrell also developed methods for plasma diagnostics.
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Within plasma physics, PIC simulation has been used successfully to study laser-plasma interactions, electron acceleration and ion heating in the auroral ionosphere, magnetohydrodynamics, magnetic reconnection, as well as ion-temperature- gradient and other microinstabilities in tokamaks, furthermore vacuum discharges, and dusty plasmas. Hybrid models may use the PIC method for the kinetic treatment of some species, while other species (that are Maxwellian) are simulated with a fluid model. PIC simulations have also been applied outside of plasma physics to problems in solid and fluid mechanics.
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The Type-M hit for 40 damage points maximum, rather than the Type-S's 30 hit points. Drone-using ships got speed-32 drones that gave and took more damage points, and fired from drone racks at a faster rate and with greater capacity. For all races, phasers upgraded with X-Technology could be overloaded with extra arming energy and produce fifty percent greater damage. They could also fire in "rapid pulse" mode as a type of Gatling phaser, tearing up fighters, drones, and plasmas.
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Sodha has done extensive research in the physical science disciplines of plasma and energy. He is credited with pioneering researches on colloidal plasmas, optics and Akhamanov's formulation and he presented papers on quantitative theory of image formation in layered media. His book, Microwave Propagation in Ferrimagnetics is reported to be the first book on the subject. He has also published 13 books including Solar Crop Drying, Solar Distillation and Solar Passive Building: Science and Design and had edited a book, Sodha Reviews of Renewable Energy Resources.
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His dissertation, entitled "Kinetic theory of equilibrium plasmas", was supervised by Edward A. Frieman, then Associate Director of the Princeton Plasma Physics Laboratory. He was a member of the technical staff of Bell Telephone Labs from 1967 to 1974. Among his notable accomplishments there was a collaboration with Akira Hasegawa on optical solitons which underpinned later advances in fiber-optic communication technology. Following his years at Bell Labs, Tappert was a Senior Research Scientist at the Courant Institute of New York University from 1974 to 1978.
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Trisops was an experimental machine for the study of magnetic confinement of plasmas with the ultimate goal of producing fusion power. The configuration was a variation of a compact toroid, a toroidal (doughnut-shaped) structure of plasma and magnetic fields with no coils penetrating the center. It lost funding in its original form in 1978. The configuration was produced by combining two individual toroids produced by two conical θ pinch guns, located at either end of a length of Pyrex pipe with a constant magnetic guide field.
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Fusion-relevant temperatures have been achieved using a variety of heating methods that were developed in the early 1970s, and in modern machines, , the major remaining issue is the confinement time. Plasmas in strong magnetic fields are subject to a number of inherent instabilities, which must be suppressed to reach useful times. One way to do this is to simply make the reactor volume larger, which reduces the rate of leakage due to classical diffusion. This is why modern designs like ITER are so large.
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Arie Andries Kruithof (1909, Zeist (NL) – 1993, Son en Breugel (NL)) was a Dutch professor of applied physics at Eindhoven University of Technology (Netherlands). Kruithof studied physics at Utrecht University, where he obtained a doctor’s degree from Leonard Ornstein in 1934.PhD dissertation at Utrecht University: (under Leonard Ornstein) At Philips, he did research on lighting systems, especially gas-discharge lamps. Later he was appointed professor of applied physics at Eindhoven University of Technology, leading the Atomic Physics group, mainly researching gas discharges and plasmas.
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After his retirement Tuck became a prominent public supporter of research into thermonuclear fusion for power generation. He also became interested in the phenomenon of ball lightning, probably because of the connection between plasmas and their role in fusion power schemes, and in 1980 he appeared in the Arthur C. Clarke's Mysterious World episode 'Clarke's Cabinet of Curiosities' where he described his experiments at Los Alamos, carried out during lunch breaks, to create ball lightning using a large storage battery of the type then used in submarines.
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A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly observable matter is composed of up quarks, down quarks and electrons. Due to a phenomenon known as color confinement, quarks are never found in isolation; they can be found only within hadrons, which include baryons (such as protons and neutrons) and mesons, or in quark–gluon plasmas.
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Ghulam Murtaza (born 3 January 1939), , is a Pakistani theoretical physicist with a specialization in the physics of ionized plasmas, and is an Emeritus Professor of physics at the Government College University in Lahore. Murtaza's work is recognizable in plasma physics and controlled nuclear fusion processes to provide a better understanding of energy propagated by the main-sequence star, the Sun. From 2000 till 2020, Murtaza served on the science faculty of the Government College University where he directed the Abdus Salam Chair in Physics.
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By late 1976 they had all but given up on them. They commissioned a report by Physical Dynamics, which outlined possible uses of such a laser, including space-based weapons. None of these seemed promising, and DARPA dropped funding for X-ray laser research in favor of the more promising free electron laser. In June 1977, two well-known Soviet researchers, Igor Sobel'man, and Vladilen Letokhov, displayed a film exposed the output of plasmas of chlorine, calcium and titanium, similar to the Utah results.
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Plasmas are confined in the axial direction by biasing the end electrodes so as to create an axial potential well that will trap charges of a given sign (the sign is assumed to be positive in the figure). In the radial direction, confinement is provided by the Lorentz force due to rotation of the plasma about the trap axis. Plasma rotation causes an inward directed Lorentz force that just balances the outward directed forces caused by the unneutralized plasma as well as the centrifugal force.
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Mima studied physics at Kyoto University and graduated with a bachelor's degree in 1968 and a PhD in 1973. He was a post-doctoral student at Hiroshima University until 1975 and then started work at Osaka University, where he became an assistant professor in 1978 and a professor in 1984. From 1995 to 1999, he was director of the Institute of Laser Engineering. There, his work involved laser fusion (experiments with the Gekko XII laser and FIREX program), free electron lasers, relativistic plasmas and laser-plasma interaction.
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Gyrokinetic ElectroMagnetic (GEM) is a gyrokinetic plasma turbulence simulation that uses the \delta f particle-in-cell method. It is used to study waves, instabilities and nonlinear behavior of tokamak fusion plasmas. Information about GEM can be found at the GEM web page. Plasma Simulation Group - Center for Integrated Plasma Studies There are two versions of GEM, one is a flux-tube version A delta-f method for gyrokinetic simulations with kinetic electrons and electromagnetic perturbuations, Y. Chen and S. Parker, J. Comput. Phys.
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Rotman wrote several classic works and papers on the interference of radar plasma on re- entry vehicles and on simulation of plasmas via a grid of thin rods which was an early inspiration for today's work on metamaterials. Rotman was awarded many honors. He was elected an IEEE Fellow in 1968 for contributions to antenna technology. He received the IEEE Centennial Medal in 1984 and the USAF Decoration for Exceptional Civilian Service in 1980, and in 2005 he received the John Kraus Antenna Award.
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During 1970–1991, he was also a Professor of Moscow State University. Since 1995, Larkin was a Professor of Physics at the University of Minnesota and a member of William I. Fine Theoretical Physics Institute. William I. Fine Institute Homepage The list of his publications (233 entries) consists of papers on condensed matter theory, theory of elementary particles, and nuclei and plasmas. A.A. Vedenov, A.I. Larkin, Equation of state of plasma, Sov. Phys. JETP 9, 806-821 (1959) Citation index of publications by A. Larkin exceeds 14,000.
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Taylor won the Institute of Physics's James Clerk Maxwell Medal and Prize in 1971, and the Max Born Medal and Prize in 1979. He then went on to win the American Physical Society's James Clerk Maxwell Prize for Plasma Physics in 1999. Taylor initiated the study of chaos in magnetic surfaces, developing several contributions to chaos theory and introducing the "standard map" (or Chirikov–Taylor map). He studied 2D-plasmas, demonstrating the inherent Bohm diffusion which had been noticed in magnetic bottles since the 1950s.
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Born in Rostock, Günter matriculated from high school in 1982. She went on to study physics at the University of Rostock where she graduated in 1987 and earned a doctorate in 1990 with a dissertation on radiation from dense plasmas. After working as a research associate in the university's department of theoretical physics, she received her postdoctoral habilitation in 1996. Her work in Rostock was complemented by periods in the United States at the University of Maryland and at the National Institute of Standards and Technology.
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The Weibel instability is a plasma instability present in homogeneous or nearly homogeneous electromagnetic plasmas which possess an anisotropy in momentum (velocity) space. This anisotropy is most generally understood as two temperatures in different directions. Burton Fried showed that this instability can be understood more simply as the superposition of many counter-streaming beams. In this sense, it is like the two-stream instability except that the perturbations are electromagnetic and result in filamentation as opposed to electrostatic perturbations which would result in charge bunching.
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However as measurements became more accurate and tokamak plasmas got hotter, discrepancies appeared. One discrepancy is that relaxations caused a much more rapid drop in the central plasma temperature of hot tokamaks than predicted by the resisive reconnection in the Kadomtsev model. Some insight into fast sawtooth crashes was provided by numerical simulations using more sophisticated model equations and by the Wesson model. Another discrepancy found was that the central safety factor was observed to be significantly less than unity immediately after some sawtooth crashes.
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Over the following two decades, Goldston led several experimental efforts studying the physics and efficacy of heating tokamak plasmas with neutral beams, discovering along the way a type of instability that could eject energetic beam ions if the neutral beam system was aimed too orthogonally with respect to the tokamak plasma. He also explored a number of other loss mechanisms for energetic ions. This proved crucial in determining the range of angles over which future neutral beam systems could access toroidal plasma configurations. Drawing upon a wide body of experimental data from most of the tokamaks then operating, Goldston developed the first widely applicable empirical scaling relationship for the confinement of energy in tokamak plasmas as a function of such parameters as the major radius, minor radius, density, current, and heating power from such sources as neutral beam systems. This scaling relationship, which came to be known as “Goldston Scaling,” provided a predictive tool for estimating the performance of tokamaks, and found wide utility, eventually forming the starting point for later energy confinement scalings based upon much larger analyses of data from successive generations of tokamaks.
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Explorer 21 was a solar cell and chemical-battery powered spacecraft instrumented for interplanetary and distant magnetospheric studies of energetic particles, cosmic rays, magnetic fields, and plasmas. Each normal telemetry sequence of 81.9 s in duration consisted of 795 data bits. After every third normal sequence there was an 81.9-s interval of rubidium vapor magnetometer analog data transmission. Initial spacecraft parameters included a local time of apogee at noon, a spin rate of 14.6 rpm, and a spin direction of 41.4-deg right ascension and 47.4-deg declination.
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While these similarity transformations capture some basic properties of plasmas, not all plasma phenomena scale in this way. Consider, for example, the degree of ionization, which is dimensionless and thus would ideally remain unchanged when the system is scaled. The number of charged particles per unit volume is proportional to the current density, which scales as x−2, whereas the number of neutral particles per unit volume scales as x−1 in this transformation, so the degree of ionization does not remain unchanged but scales as x−1.
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In this context, matter has quantum properties while gravity remains classical even at the fundamental level. The Schrödinger–Newton equation was therefore also suggested as a way to test the necessity of quantum gravity. In a third context, the Schrödinger–Newton equation appears as a Hartree approximation for the mutual gravitational interaction in a system of a large number of particles. In this context, a corresponding equation for the electromagnetic Coulomb interaction was suggested by Philippe Choquard at the 1976 Symposium on Coulomb Systems in Lausanne to describe one-component plasmas.
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Carburization of steel involves a heat treatment of the metallic surface using a source of carbon. Carburization can be used to increase the surface hardness of low carbon steel. Early carburization used a direct application of charcoal packed around the sample to be treated (initially referred to as case hardening), but modern techniques use carbon-bearing gases or plasmas (such as carbon dioxide or methane). The process depends primarily upon ambient gas composition and furnace temperature, which must be carefully controlled, as the heat may also impact the microstructure of the remainder of the material.
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The most common materials are photorefractive crystals, but in semiconductors or semiconductor heterostructures (such as quantum wells), atomic vapors and gases, plasmas and even liquids, it was possible to generate holograms. A particularly promising application is optical phase conjugation. It allows the removal of the wavefront distortions a light beam receives when passing through an aberrating medium, by sending it back through the same aberrating medium with a conjugated phase. This is useful, for example, in free-space optical communications to compensate for atmospheric turbulence (the phenomenon that gives rise to the twinkling of starlight).
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The Madison Symmetric Torus (MST) is a reversed field pinch (RFP) physics experiment with applications to both fusion energy research and astrophysical plasmas located at University of Wisconsin-Madison. RFPs are significantly different from tokamaks (the most popular magnetic confinement scheme) in that they tend to have a higher power density and better confinement characteristics for a given average magnetic field. RFPs also tend to be dominated by non-ideal phenomena and turbulent effects. MST is one of the sites in the Center for Magnetic Self Organization (CMSO).
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Sandia National Laboratory is currently investigating a z-pinch as a possible ignition source for inertial confinement fusion. On its "Z machine", Sandia can achieve dense, high temperature plasmas by firing fast, 100-nanosecond current pulses exceeding 20 million amps through hundreds of tungsten wires with diameters on the order of tens of micrometres. The LTD is currently being investigated as a driver for the next generation of high power accelerators. Sandia's roadmap includes another future Z machine version called ZN (Z Neutron) to test higher yields in fusion power and automation systems.
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Basic remote plasma diagram A remote plasma refers to a plasma that is spatially separated from the external electromagnetic fields that initiate the discharge. An afterglow is a remote plasma if the plasma is channeled away from the original plasma source. An advantage that remote plasma has over temporal plasma is that remote plasma can be used as a continuous plasma source and thus has more applications in supplying reagent ions for most systems. Remote plasmas are often used in the field of analytical chemistry when a constant stream of ions is required.
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Bulanov investigated the idea of relativistic mirrors for generating X-rays, whereby a laser beam is reflected by plasma waves and is split up by nonlinear interactions to form a thin layer of relativistic electrons. They were intended to be an alternative to synchrotron radiation sources and free electron lasers, and were used in the development of compact radiation sources and for basic research in quantum electrodynamics (e.g. electron-positron pair production in vacuum). Bulanov has also worked on particle acceleration using laser plasmas and developed a laser ion accelerator intended for cancer therapy.
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In 1956, while planning a well publicised state visit by Nikita Khrushchev and Nikolai Bulganin to the UK, the Harwell researchers received an offer from Soviet scientist Igor Kurchatov to give a talk. They were surprised when he began his talk on "the possibility of producing thermonuclear reactions in a gaseous discharge". Kurchatov's speech revealed the Soviet efforts to produce fast pinch devices similar to the American designs, and their problems with instabilities in the plasmas. Kurchatov noted that they had also seen neutrons being released, and had initially believed them to be from fusion.
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Carl-Gunne Fälthammar (born 4 December 1931, Markaryd, Sweden) is Professor Emeritus at the Royal Institute of Technology in Stockholm, Sweden, specialising in space and plasma physics in the School of Electrical Engineering. He succeeded Hannes Alfvén as Professor of Plasma Physics in 1975.Carl-Gunne Fälthammar Home page at the KTH School of Electrical Engineering His research interests include plasma electrodynamics, with application to space and astrophysical plasmas, especially in the context of auroral and magnetospheric physics. He is also the Associate Editor of the journal Astrophysics and Space Science.
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It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules. Since the distance between the Zeeman sub- levels is a function of magnetic field strength, this effect can be used to measure magnetic field strength, e.g. that of the Sun and other stars or in laboratory plasmas.
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Magnetospheres are formed by the solar wind plasma flow around planets with an intrinsic magnetic field (Mercury, Earth, Jupiter, Saturn, Uranus, and Neptune), although planets and moons lacking magnetic fields may sometimes form magnetosphere-like plasma structures. The ionospheres of weakly magnetized planets such as Venus and Mars set up currents that partially deflect the solar wind flow around the planet. Although magnetospheric plasmas have very low densities; e.g. near Jupiter's moon Europa, plasma pressures are about 10−13 bar, compared to 1 bar at Earth's surface, and are responsible for magnetospheric dynamics and emissions.
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Furthermore, states near such thermal equilibria can be more easily controlled experimentally and departures from equilibrium studied with precision. When a neutral plasma is cooled, it simply recombines; but a plasma with a single sign of charge can be cooled without recombination. Malmberg constructed a trap for a pure electron plasma with walls at 4.2 K. Cyclotron radiation from the electrons then cooled the plasma to a few Kelvin. Theory argued that electron-electron collisions in such a strongly magnetized and low temperature plasma would be qualitatively different than those in warmer plasmas.
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This includes ever more precise studies of antihydrogen and comparison with the properties of hydrogen and formation of the di-positronium molecule (Ps_2, e^+e^-e^+e^-) predicted by J. A. Wheeler in 1946. The Penning–Malmberg trap technology is now being used to create a new generation of high-quality positroniumatom (e^+e^-) beams for atomic physics studies. In the broader view, Malmberg’s seminal studies with trapped single-component and non-neutral plasmas have stimulated vibrant sub-fields of plasma physics with surprisingly broad impacts in the wider world of physics.
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In 1962, Stix was elected Chair of the Division of Plasma Physics of the American Physical Society. He received a Guggenheim Fellowship in 1969, leading to the first of his three sabbaticals at the Weizmann Institute of Science in Israel. In 1980, the American Physical Society awarded Stix its highest honor in the plasma physics field, the James Clerk Maxwell Prize for Plasma Physics, for his pioneering role in developing and formalizing the theory of wave propagation and wave heating in plasmas. In 1999, he received the Lifetime Achievement Award by Fusion Power Associates.
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Zwicker was born in New York City. Raised in Englewood, New Jersey, where he graduated from Dwight Morrow High School in 1982, he went on to achieve his B.A. in physics from Bard College in 1986, and his M.A. and Ph.D., both also in physics, from Johns Hopkins University in 1992. His dissertation was entitled "Soft X-Ray Spectroscopy of Magnetically Confined Fusion Plasmas Using Flat Multilayer Mirrors as Dispersive Elements". Zwicker's post-doctoral work focused on fusion energy research at the Princeton Plasma Physics Laboratory, at Oak Ridge National Laboratory, and internationally.
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In 1976, he was involved in the design of the first laser fusion experiments with the Cyclops laser. In 1983, he was deputy program manager for theory and target design in the ICF program of the LLNL. In 1990, he became head of the Nova Laser program to demonstrate the use of a 1 to 2 megajoule laser for inertial fusion. After the ICF research at LLNL became declassified in 1993, Lindl wrote an overview article in Physics of Plasmas, which then led to his book on inertial fusion in 1997.
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It is the electric-field analogue of the Zeeman effect, where a spectral line is split into several components due to the presence of the magnetic field. Although initially coined for the static case, it is also used in the wider context to describe the effect of time-dependent electric fields. In particular, the Stark effect is responsible for the pressure broadening (Stark broadening) of spectral lines by charged particles in plasmas. For most spectral lines, the Stark effect is either linear (proportional to the applied electric field) or quadratic with a high accuracy.
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Within these areas scientists lead individual experiments and research projects organised in about 25 project teams. The research topics pursued at MPE range from the physics of cosmic plasmas and of stars to the physics and chemistry of interstellar matter, from star formation and nucleosynthesis to extragalactic astrophysics and cosmology. Many experiments of the Max-Planck-Institut für extraterrestrische Physik (MPE) have to be carried out above the dense Earth's atmosphere using aircraft, rockets, satellites and space probes. In the early days experiments were also flown on balloons.
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During his doctoral studies, Vargas-Blanco participated in other scientific activities such as the calibration and maintenance of the electronic cyclotron emission diagnosis for the measurement of plasma temperature and activities within the electronic cyclotron resonance heating group of the Stellarator TJ-II. Stellarator of Costa Rica 1 (SCR-1). Photo Ruth Garita, OCM-TEC. Prior to his return to Costa Rica, Vargas-Blanco succeeded in having the CIEMAT and the Tecnológico de Costa Rica sign a collaboration agreement to promote research in nuclear fusion plasmas between the two institutions.
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He served as director of UCLA's Center for Plasma Physics and Fusion Engineering from 1976–87. He was associate director of the Institute for Plasma and Fusion Research from 1989–91, principal scientist with the institute since 1989 and the institute's interim director. John was a leading figure in the plasma physics community for more than four decades, with his contributions to science spanning all of plasma physics. He performed seminal work on magnetic fusion, inertial confinement fusion, space plasmas, plasma astrophysics, free-electron lasers, and basic plasma physics.
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An electrodynamic tether can be described as a type of thermodynamically "open system". Electrodynamic tether circuits cannot be completed by simply using another wire, since another tether will develop a similar voltage. Fortunately, the Earth's magnetosphere is not "empty", and, in near-Earth regions (especially near the Earth's atmosphere) there exist highly electrically conductive plasmas which are kept partially ionized by solar radiation or other radiant energy. The electron and ion density varies according to various factors, such as the location, altitude, season, sunspot cycle, and contamination levels.
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Lightning as an example of plasma present at Earth's surface: Typically, lightning discharges 30 kiloamperes at up to 100 megavolts, and emits radio waves, light, X- and even gamma rays.See Flashes in the Sky: Earth's Gamma-Ray Bursts Triggered by Lightning Plasma temperatures can approach 30000 K and electron densities may exceed 1024 m−3. Since plasmas are very good electrical conductors, electric potentials play an important role. The average potential in the space between charged particles, independent of how it can be measured, is called the "plasma potential", or the "space potential".
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An inductively coupled plasma is a plasma that is energized (ionized) by inductively heating the gas with an electromagnetic coil, and contains a sufficient concentration of ions and electrons to make the gas electrically conductive. Even a partially ionized gas in which as little as 1% of the particles are ionized can have the characteristics of a plasma (i.e., response to magnetic fields and high electrical conductivity). The plasmas used in spectrochemical analysis are essentially electrically neutral, with each positive charge on an ion balanced by a free electron.
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This is an energy distribution comparison of thermalized and non-thermalized ions The primary problem that Rider has raised is the thermalization of ions. Rider argued that, in a quasineutral plasma where all the positives and negatives are distributed equally, the ions will interact. As they do, they exchange energy, causing their energy to spread out (in a Wiener process) heading to a bell curve (or Gaussian function) of energy. Rider focused his arguments within the ion population and did not address electron-to-ion energy exchange or non-thermal plasmas.
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The free proton (a proton not bound to nucleons or electrons) is a stable particle that has not been observed to break down spontaneously to other particles. Free protons are found naturally in a number of situations in which energies or temperatures are high enough to separate them from electrons, for which they have some affinity. Free protons exist in plasmas in which temperatures are too high to allow them to combine with electrons. Free protons of high energy and velocity make up 90% of cosmic rays, which propagate in vacuum for interstellar distances.
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In the group of astrophysical plasmas, our scientist perform studies about the dynamic configuration and structures of the corona through the analysis of magnetic arcs and prominences, the formation of voids that remain in the plasma due to the interaction of nonlinear waves, the formation of very energetic shock wave capable of sweeping the chromosphere along a whole quadrant, etc. The team also analyse the interaction of stellar winds with the magnetosphere of exoplanets, and they model the morphology of supernova remnants affected by instabilities and the influence of the magnetic field.
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The solar observatory Einstein Tower and Observatory for Solar Radio Astronomy were affiliated later. One part of the scientific activities concerned cosmic magnetic fields and cosmic dynamos, phenomena of turbulence, magnetic and eruptive processes on the Sun, explosive energy dissipation processes in plasmas, variable stars and stellar activity. Another part was directed to the early phases of cosmic evolution and the origin of structures in the Universe, large-scale structures up to those of superclusters and to active galaxies. In this connection special methods of image processing have been developed.
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The Laboratoire Plasma et Conversion d'Energie (LAPLACE), Toulouse is a Centre National de la Recherche Scientifique (CNRS) laboratory, operated jointly by the CNRS, the University of Toulouse and the Institut National Polytechnique of Toulouse. This facility is located near other important higher education facilities in Toulouse, France: the Paul Sabatier University, SUPAERO, the ENAC, the INSA, as well as other research centers (the ONERA and the CNES). Research at LAPLACE is multidisplinary by nature. LAPLACE has active research programs in the following areas : Technological plasmas and their applications.
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He remained there for nearly three decades, working on anti-missile defence and became chief scientific officer. He was a member of a number of commissions and committees which assessed theses and awarded prizes. In addition to his nuclear weapon and defence research, he wrote papers on the quasilinear theory of plasma turbulence, cosmic plasmas, gravitational spinors, laser-driven thermonuclear fusion and long-range fields Amongst his hobbies, he enjoyed playing chess and piano (particularly Chopin and Beethoven). He was also known for writing amusing poetic portraits of friends and colleagues.
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Journal of Physics D: Applied Physics is a peer-reviewed scientific journal published by IOP Publishing, a subsidiary of the Institute of Physics in the United Kingdom. It was established in 1968 from the division of the earlier title, Proceedings of the Physical Society. It has a broad coverage, including five main focus areas: magnetism; photonics and semiconductors; plasmas and plasma-surface interactions; applied surfaces and interfaces; structure and properties of matter and renewable energy/sustainability. The current editor- in-chief is Joan Ramón Morante (Catalonia Institute for Energy Research).
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The group that he created and leads is a pioneer in the miniaturization of dense plasma focus devices which can reproduce, on a scale basis, similar physics as the ones obtained in large devices which are only available in large laboratories of the world. Due to Soto´s contributions, it is possible to develop relevant research in dense transient plasmas using small devices. He received the B.S., M.S. and Ph.D. degrees in Physics in 1989, 1990 and 1993, respectively, from the Pontificia Universidad Católica de Chile. His Ph.D. thesis was advised by Hernán Chuaqui.
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In experiments on single species plasmas, plasma rotation rates in the tens of kHz range are not uncommon, even in the slow rotation mode. This rapid rotation is necessary to provide the confining radial Lorentz force for the plasma. However, if there is neutral gas in the trap, collisions between the plasma and the gas cause the plasma rotation to slow, leading to radial expansion of the plasma until it comes in contact with the surrounding electrodes and is lost. This loss process can be alleviated by operating the trap in an ultra high vacuum.
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Since April 2008 he is honorary professor (W3) at the Ruprecht-Karls-University Heidelberg, Germany. In November 2008 he was elected as a Fellow of the American Physical Society (APS). After his first term (2012-2014), he was again vice chairman of the advisory committee "Hadrons and Nuclei" of the Federal Ministry of Education and Research (BMBF) from 2018 to March 2020. During the membership period 2012-2019 Klaus Blaum was a member of the DFG (German Research Foundation) Review Board 308 "Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas".
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According to the theory of relativity, no information can travel faster than the speed of light in vacuum, but this does not mean that the refractive index cannot be less than 1. The refractive index measures the phase velocity of light, which does not carry information. The phase velocity is the speed at which the crests of the wave move and can be faster than the speed of light in vacuum, and thereby give a refractive index below 1. This can occur close to resonance frequencies, for absorbing media, in plasmas, and for X-rays.
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Because the fusion reactions release so much energy, even a small number of these reactions can release enough energy to keep the gas at the required temperature. In 1944, Enrico Fermi demonstrated that this would occur at a bulk temperature of about 50 million Celsius, still very hot but within the range of existing experimental systems. The key problem was confining such a plasma; no material container could withstand those temperatures. But because plasmas are electrically conductive, they are subject to electric and magnetic fields which provide a number of solutions.
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He also mentored 18 research scholars, including two from Southampton University, in their studies. Bhawalkar is credited with pioneering research on Lasers in India and was the initiator of a new method for measuring weak lensing in gases by employing a Gaussian beam which has since been incorporated in Photothermal spectroscopy. His development of an Nd Glass laser chain for generating 10GW of pulsed power has assisted the subsequent experiments on laser-produced plasmas. He has also contributed to the development of biological and medical applications of lasers.
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In 1958, Lodewijk Woltjer, working on astrophysical plasmas, noted that H is conserved, which implies that a twisty field will attempt to maintain its twistiness even with external forces being applied to it. Starting in 1959, Alfvén and a team including Lindberg, Mitlid and Jacobsen built a device to create balls of plasma for study. This device was identical to modern "coaxial injector" devices (see below) and the experimenters were surprised to find a number of interesting behaviors. Among these was the creation of stable rings of plasma.
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The focus of the research activity was on designs, interactions and materials required for electromagnetic launchers. In 1999, a collaboration between ARL and IAT led to the development of a radiometric method of measuring the temperature distribution of railgun armatures during a pulsed electrical discharge without disturbing the magnetic field. In 2001, ARL became the first to obtain a set of accuracy data on electromagnetic gun-launched projectiles using jump tests. In 2004, ARL researchers published papers examining the interaction of high temperature plasmas for the purpose of developing efficient railgun igniters.
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If successful it was to be followed by similar devices, eventually including a demonstration power reactor (e.g. ITER), burning deuterium-tritium fuel. NSTX produced a spherical plasma with a hole through its center (a "cored apple" profile; see MAST), different from the doughnut- shaped (toroidal) plasmas of conventional tokamaks. The low aspect ratio A (that is, an R/a of 1.31, with the major radius R of 0.85 m and the minor radius a of 0.65 m) experimental NSTX device had several advantages including plasma stability through improved confinement.
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Design challenges include the toroidal and poloidal field coils, vacuum vessels and plasma-facing components. This plasma configuration can confine a higher pressure plasma than a doughnut tokamak of high aspect ratio for a given, confinement magnetic field strength. Since the amount of fusion power produced is proportional to the square of the plasma pressure, the use of spherically shaped plasmas could allow the development of smaller, more economical and more stable fusion reactors. NSTX's attractiveness may be further enhanced by its ability to trap a high "bootstrap" electric current.
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The value of the method lies in its ability to calculate the interacting pair distribution functions g(r) at zero and finite temperatures. Comparison of the calculated g(r) with results from Quantum Monte Carlo show remarkable agreement, even for very strongly correlated systems. The interacting pair- distribution functions obtained from CHNC have been used to calculate the exchange-correlation energies, Landau parameters of Fermi liquids and other quantities of interest in many-body physics and density functional theory, as well as in the theory of hot plasmas.
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The closed nature of the magnetic lines means that unless the plasma separates from the guiding magnetic field downstream, it will turn around along the field lines back to the thruster. This would defeat the propulsive purpose of the magnetic nozzle, as the returning plasma would cancel thrust and could endanger the integrity of the spacecraft and the plasma thruster. A plasma detachment mechanism is therefore necessary for the correct operation of the magnetic nozzle.Ahedo, E., Merino, M., On plasma detachment in propulsive magnetic nozzles, Physics of Plasmas, Vol.
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This led to hot spots on the pellet which were imprinted into the imploding plasma, seeding Rayleigh–Taylor instabilities and thereby mixing the plasma so the center did not collapse uniformly.Moody et all, "Beam smoothing effects on stimulated Raman and Brillouin backscattering in laser-produced plasmas", Journal of Fusion Energy, Vol. 12, No. 3, September 1993, , pp. 323-330 Nevertheless, Nova remained a useful instrument even in its original form, and the main target chamber and beamlines were used for many years even after it was modified as outlined below.
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Today Haselgrove's equations are widely used in scientific investigations involving radio propagation in slowly varying plasmas, and therefore have found much applicability in exploration and utilization of the Earth's ionosphere. Here they have also been used to represent the radio propagation element of practical systems providing high frequency communication, direction finding and over-the-horizon radar. For a recent broad discussion on ray tracing in the ionosphere see Bennett et al.J. A. Bennett, P. L. Dyson, R. J. Norman, Progress in Radio Ray Tracing in the Ionosphere, The Radio Science Bulletin, September 2004, p. 81.
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The q profile in a reversed field pinch The poloidal field in a reversed field pinch A reversed-field pinch (RFP) is a device used to produce and contain near-thermonuclear plasmas. It is a toroidal pinch which uses a unique magnetic field configuration as a scheme to magnetically confine a plasma, primarily to study magnetic confinement fusion. Its magnetic geometry is somewhat different from that of the more common tokamak. As one moves out radially, the portion of the magnetic field pointing toroidally reverses its direction, giving rise to the term reversed field.
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Resistive wall modes (RWM) develop in plasmas that require the presence of a perfectly conducting wall for stability. RWM stability is a key issue for many magnetic configurations. Moderate beta values are possible without a nearby wall in the tokamak, stellarator, and other configurations, but a nearby conducting wall can significantly improve ideal kink mode stability in most configurations, including the tokamak, ST, reversed field pinch (RFP), spheromak, and possibly the FRC. In the advanced tokamak and ST, wall stabilization is critical for operation with a large bootstrap fraction.
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Since 1989, Shukla has been a co-organizer/director of the plasma physics activities (Summer Colleges and Workshops in Plasma Physics) at the Abdus Salam International Centre for Theoretical Physics (AS-ICTP), Trieste (Italy), Chairman of the International Advisory Committee of the International Conference on Physics of Dusty Plasmas (ICPDP), and International Advisory Committee member of the International Congress on Plasma Physics (ICPP). He has presented over 130 keynote, plenary, tutorial, and topical lectures in international conferences, including European Physical Society, American Physical Society, ICPP, ICPDP, Summer Colleges and Workshops at the AS-ICTP. Shukla has significantly contributed to education, as well as to the development of basic and applied physics worldwide; specifically, in developing countries across the globe. He has served (2008-2011) as Chairman of the International Union of Pure and Applied Physics (IUPAP) C.16 Commission on Plasma Physics, and serving (since 2008) as Chairman of the Scientific Council of the Emerging Nations Science Foundation (Trieste, Italy), as Editor-in-Chief of J. Plasma Physics (Cambridge University Press, UK), as Editorial Board Member of Physical Review E (American Physical Society), as Associate Editor of Physics of Plasmas (American Institute of Physics), and as International Advisory Panel of Plasma Physics and Controlled Fusion (Institute of Physics, Bristol, UK).
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Numerical experiments with the code have also resulted in the compilation of a global scaling law indicating that the well-known neutron saturation effect is better correlated to a scaling deterioration mechanism. This is due to the increasing dominance of the axial phase dynamic resistance as capacitor bank impedance decreases with increasing bank energy (capacitance). In principle, the resistive saturation could be overcome by operating the pulse power system at a higher voltage. The International Centre for Dense Magnetised Plasmas (ICDMP) in Warsaw Poland, operates several plasma focus machines for an international research and training programme.
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Among these machines is one with energy capacity of 1 MJ making it one of the largest plasma focus devices in the world. In Argentina there is an Inter-institutional Program for Plasma Focus Research since 1996, coordinated by a National Laboratory of Dense Magnetized Plasmas (www.pladema.net) in Tandil, Buenos Aires. The Program also cooperates with the Chilean Nuclear Energy Commission, and networks the Argentine National Energy Commission, the Scientific Council of Buenos Aires, the University of Center, the University of Mar del Plata, The University of Rosario, and the Institute of Plasma Physics of the University of Buenos Aires.
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At UCLA, Joshi has built a strong research group that has done pioneering work in the areas of laser-plasma instabilities, plasma-based light sources, laser fusion and basic plasma experiments. Joshi has made many fundamental contributions to the understanding of extremely nonlinear optical effects in plasmas. Most notable including his first experimental demonstration of four-wave mixing, stimulated Raman forward instability, resonant self-focusing, frequency upshifting by ionization fronts and nonlinear coupling between electron-plasma waves. His group is best known, however, for developing the field of plasma-based particle accelerators over the past three decades.
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In plasma physics, an ion acoustic wave is one type of longitudinal oscillation of the ions and electrons in a plasma, much like acoustic waves traveling in neutral gas. However, because the waves propagate through positively charged ions, ion acoustic waves can interact with their electromagnetic fields, as well as simple collisions. In plasmas, ion acoustic waves are frequently referred to as acoustic waves or even just sound waves. They commonly govern the evolution of mass density, for instance due to pressure gradients, on time scales longer than the frequency corresponding to the relevant length scale.
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The antiprotons lose energy and equilibrate with the cold electrons by Coulomb interaction. The electrons are ejected before mixing the antiprotons with positrons. Each AD shot results in about cold antiprotons for interaction experiments. The positron accumulator slows, traps and accumulates positrons emitted from a radioactive source (1. Bq 22Na). Accumulation for 300 s yields 1. positrons, 50% of which are successfully transferred to the mixing trap, where they cool by synchrotron radiation. The mixing trap has the axial potential configuration of a nested Penning trap (Fig. 1b), which permits two plasmas of opposite charge to come into contact.
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13 The other advantages have to do with the stability of the plasma. Since the earliest days of fusion research, the problem in making a useful system has been a number of plasma instabilities that only appeared as the operating conditions moved ever closer to useful ones for fusion power. In 1954 Edward Teller hosted a meeting exploring some of these issues, and noted that he felt plasmas would be inherently more stable if they were following convex lines of magnetic force, rather than concave.Robin Herman, "Fusion: The Search for Endless Energy", Cambridge University Press, 1990, pg.
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HIDRA is probably the most well traveled fusion devices in the world. From its beginnings in France it has operated in 3 countries and 4 cities. The research goals of the device have dramatically changed over the years from doing wave heating studies, to being a testbed for one of the world's most sophisticated fusion devices and now to studying the way plasmas interact with the inside wall and materials of fusion devices. In fact it will be the first toroidal fusion-relevant device that will be dedicated to the study of plasma wall (PWI) and plasma material interactions (PMI).
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Mixing studies are tests performed on blood plasma of patients or test subjects to distinguish factor deficiencies from factor inhibitors, such as lupus anticoagulant, or specific factor inhibitors, such as antibodies directed against factor VIII. The basic purpose of these tests is to determine the cause of prolongation of Prothrombin Time (PT), Partial Thromboplastin Time, or sometimes of thrombin time (TT). Mixing studies take advantage of the fact that factor levels that are 50 percent of normal should give a normal Prothrombin time (PT) or Partial thromboplastin time (PTT) result. Factor deficient plasmas (Adsorbed Plasma & Aged Plasma, etc.) are used in mixing studies.
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Kaw received his Ph.D. at the age of 18, following which he completed his PostDoc at Princeton University. He had been the founding director of the Institute for Plasma Research and served the institute as the director from 1986 to 2012. He was awarded the prestigious Padma Shri award, India's fourth-highest honor, in 1985 and Shanti Swarup Bhatnagar Award in 1986. On 28 December 2016, he was awarded the Subrahmanyan Chandrasekhar Prize of Plasma Physics for his seminal contributions in the areas of laser-plasma interactions, strongly coupled dusty plasmas, and turbulence, nonlinear effect in magnetic fusion devices.
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She is now the William L. Kraushaar Professor of Astronomy and Physics at the University of Wisconsin–Madison. Zweibel is a founding member and former director of the Center of Magnetic Self-Organization of the National Science Foundation (NSF) and of the Department of Energy (DOE). In 1991, she was elected a Fellow of the American Physical Society. In 2016, she received the James Clerk Maxwell Prize for Plasma Physics for "seminal research on the energetics, stability, and dynamics of astrophysical plasmas, including those related to stars and galaxies, and for leadership in linking plasma and other astrophysical phenomena".
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Many plasma physicists feel more comfortable with proud probes, which have a longer tradition and possibly are less perturbed by electron saturation effects, although this is disputed. Flush-mounted probes, on the other hand, being part of the wall, are less perturbative. Knowledge of the field angle is necessary with proud probes to determine the fluxes to the wall, whereas it is necessary with flush-mounted probes to determine the density. In very hot and dense plasmas, as found in fusion research, it is often necessary to limit the thermal load to the probe by limiting the exposure time.
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This property is exploited in the use of so-called "grease pens," which apply a line of grease to the surface of a suspect diamond simulant. Diamond surfaces are hydrophobic when the surface carbon atoms terminate with a hydrogen atom and hydrophilic when the surface atoms terminate with an oxygen atom or hydroxyl radical. Treatment with gases or plasmas containing the appropriate gas, at temperatures of 450 °C or higher, can change the surface property completely. Naturally occurring diamonds have a surface with less than a half monolayer coverage of oxygen, the balance being hydrogen and the behavior is moderately hydrophobic.
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In plasma physics, ambipolar diffusion is closely related to the concept of quasineutrality. In most plasmas, the forces acting on the ions are different from those acting on the electrons, so naively one would expect one species to be transported faster than the other, whether by diffusion or convection or some other process. If such differential transport has a divergence, then it results in a change of the charge density. The latter will in turn create an electric field that can alter the transport of one or both species in such a way that they become equal.
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Thonemann continued working on the idea and began a rigorous programme to explore the basic physics of plasmas in a magnetic field. Starting with linear tubes and mercury gas, he found that the current tended to expand outward through the plasma until it touched the walls of the container (see skin effect). He countered this with the addition of small electromagnets outside the tube, which pushed back against the current and kept it centred. By 1949, he had moved on from the glass tubes to a larger copper torus, in which he was able to demonstrate a stable pinched plasma.
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Curtis Bruce Tarter is an American physicist. He was director of the Lawrence Livermore National Laboratory from 1994 to 2002. He received his bachelor's degree in physics from the Massachusetts Institute of Technology and a Ph.D. from Cornell University. Tarter became a Fellow of the American Physical Society in 1997, having been nominated by their Division of Astrophysics, for his pioneering research on the physics of photo-ionized plasmas near astrophysical and laboratory x-ray sources and for his leadership of the Lawrence Livermore National Laboratory, maintaining the highest scientific integrity for this major US institution in a time of intense change.
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Malmberg measured the equipartition rate between electron velocity components parallel to and perpendicular to the magnetic field and confirmed the striking prediction that it decreases exponentially with decreasing temperature. Malmberg and Thomas Michael O'Neil predicted that a very cold, single-species plasma would undergo a phase transition to a body-centered cubic crystalline state. Later, John Bollinger and collaborators created such a state by laser cooling a plasma of singly ionized beryllium ions to temperatures of a few millikelvin. In other experiments, trapped pure electron plasmas are used to model the two- dimensional (2D) vortex dynamics expected for an ideal fluid.
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Rathke stated, "However, while solutions of the Schrödinger equation with n<1 indeed exist, they are not square integrable. This violates not only an axiom of quantum mechanics, but in practical terms prohibits that these solutions can in any way describe the probability density of a particle." In the same year, the Journal of Applied Physics published a critique by A.V. Phelps of the 2004 article, "Water bath calorimetric study of excess heat generation in resonant transfer plasmas" by J. Phillips, R. Mills and X. Chen. Phelps criticized both the calorimetric techniques and the underlying theory described in the Phillips/Mills/Chen article.
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Plasma, often called the fourth state of matter, is an ionized gas containing positive ions and negative ions or electrons, but is approximately charge neutral on the whole. The plasma sources used for plasma medicine are generally low temperature plasmas, and they generate ions, chemically reactive atoms and molecules, and UV-photons. These plasma-generated active species are useful for several bio-medical applications such as sterilization of implants and surgical instruments as well as modifying biomaterial surface properties. Sensitive applications of plasma, like subjecting human body or internal organs to plasma treatment for medical purposes, are also possible.
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The Plasma Science and Fusion Center (PSFC) at the Massachusetts Institute of Technology (MIT) is a university research center for the study of plasmas, fusion science and technology. It was originally founded in 1976 as the Plasma Fusion Center (PFC) at the request and with the collaboration of the U.S. Department of Energy. The original grant was for construction and operation of a tokamak reactor Alcator A, the first in a series of small, high-field tokamaks, followed by Alcator C (1978) and Alcator C-Mod (1993). MIT's most recent tokamak, Alcator C-Mod, ran from 1993 to 2016.
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Since the beginning of the 1990s, he has been leading a research program to research magnetic reconnection at the PPPL (Magnetic Reconnection Experiment, MRX) with applications both on fusion plasmas and in astrophysics. He is a Fellow of the American Physical Society in 1985, received the John Dawson Award for Excellence in Plasma Physics Research from APS in 2002 and the Kaul Prize from Princeton University in 2003. In 2015, he received the James Clerk Maxwell Prize for Plasma Physics for his research on reconnection and as a pioneer in laboratory plasma physics for astrophysics. He has published over 200 scientific publications.
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Forbidden emission lines have been observed in extremely low-density gases and plasmas, either in outer space or in the extreme upper atmosphere of the Earth. In space environments, densities may be only a few atoms per cubic centimetre, making atomic collisions unlikely. Under such conditions, once an atom or molecule has been excited for any reason into a meta-stable state, then it is almost certain to decay by emitting a forbidden-line photon. Since meta-stable states are rather common, forbidden transitions account for a significant percentage of the photons emitted by the ultra-low density gas in space.
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This allowed him in 2009 to continue conducting research in the field of nuclear fusion in Costa Rica with the dream of creating a laboratory and building a Stellarator device. Working towards his goals in plasma research, Vargas-Blanco founded in 2008 the Grupo de Plasmas y Aplicaciones in the Tecnologico de Costa Rica (TEC), and began the purchase and acquisition of scientific equipment. In 2009, the Project Stellarator of Costa Rica 1 (SCR-1) was launched with a group of enthusiastic students. The aim was to build the first device of its kind in Latin America.
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The Schwinger effect is a predicted physical phenomenon whereby matter is created by a strong electric field in which electron-positron pairs are spontaneously created in the presence of an electric field, thereby causing the decay of the electric field. Recent experimental advances raised hope that lasers could soon achieve intensities closer to the order needed for VARIES, which would likely be in the Petawatt range. Pions formed from the annihilation would have to be directed for thrust by magnetic nozzles, which could be superconducting magnets. Antimatter could be stored as non-neutral plasmas or as a neutral gas.
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Plasma injector Plasma injectors provide the fuel supply for the MTF power plant, injecting a deuterium-tritium plasma into the compression chamber. Compact toroid plasmas are formed by a coaxial Marshal gun (a type of plasma railgun), with magnetic fields supported by internal plasma currents and eddy currents in the flux conserver wall.Russ Ivanov, Patrick Carle, Neil Carter, Ken Jensen, Stephen Howard, Michel Laberge, Alex Mossman, Peter O’Shea, Adrian Wong, William Young "SPECTOR 1 Plasma as a Target for Adiabatic Compression " Poster presented at the 58th Annual Meeting of the APS Division of Plasma Physics 31 October – 4 November 2016. San Jose, California.
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He investigates the influence of structure and termination of the surface on the underlying spin centers and their properties. In 2016 he worked on the miniaturization of conventional fuel cell concepts by maximizing electrochemical active surface by using carbon nanowalls. By using innovative plasma processes and catalyst or electrolyte materials, the electrode n of the micro fuel cells' electrochemical performance was specifically improved. In addition to material synthesis, surface modifications by plasma processes and the characterization of these plasmas also belong to his field of activity with different methods such as optical emission spectroscopy and mass spectrometry.
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Since 2007, he has been a professor of Physics & Space Sciences at the Florida Institute of Technology. His academic rank is Distinguished Research Professor. He is temporarily stationed at NASA Headquarters in Washington DC where he is the Space Sciences Education Manager for NASA's Science Mission Directorate via the Intergovernmental Personnel Act Mobility Program. His best known scientific contributions are research on the transfer of mass and energy through the Sun's atmosphere; the development of space-borne observatories for studying astrophysical plasmas and dark energy; and the development of transformative technologies in ultraviolet optics, detectors, computer chips, and ion propulsion.
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PK-3 Plus logo The Plasmakristall-3 Plus (PK-3 Plus) laboratory was a joint Russian-German laboratory for the investigation of dusty/complex plasmas on board the International Space Station (ISS), with the principal investigators at the German Max Planck Institute for Extraterrestrial Physics and the Russian Institute for High Energy Densities. It was the successor to the PKE Nefedov experiment with improvements in hardware, diagnostics and software. The laboratory was launched in December 2005 and was operated for the first time in January 2006. It was used in 21 missions until it was deorbited in 2013.
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The safety factor, labeled q or q(r), is the ratio of the times a particular magnetic field line travels around a toroidal confinement area's "long way" (toroidally) to the "short way" (poloidally). The term "safety" refers to the resulting stability of the plasma; plasmas that rotate around the torus poloidally about the same number of times as toroidally are inherently less susceptible to certain instabilities. The term is most commonly used when referring to tokamak devices. Although the same considerations apply in stellarators, by convention the inverse value is used, the rotational transform, or i.
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Measurements with electric probes, called Langmuir probes, are the oldest and most often used procedures for low-temperature plasmas. The method was developed by Irving Langmuir and his co-workers in the 1920s, and has since been further developed in order to extend its applicability to more general conditions than those presumed by Langmuir. Langmuir probe measurements are based on the estimation of current versus voltage characteristics of a circuit consisting of two metallic electrodes that are both immersed in the plasma under study. Two cases are of interest: (a) The surface areas of the two electrodes differ by several orders of magnitude.
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In March 2015, the upgraded C-2U with edge-biasing beams showed a 10-fold improvement in lifetime, with FRCs heated to 10 million degrees Celsius and lasting 5 milliseconds with no sign of decay. The C-2U functions by firing two donut shaped plasmas at each other at 1 million kilometers per hour, the result is a cigar-shaped FRC as much as 3 meters long and 40 centimeters across. The plasma was controlled with magnetic fields generated by electrodes and magnets at each end of the tube. The upgraded particle beam system provided 10 megawatts of power.
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The Bohr–van Leeuwen theorem is useful in several applications including plasma physics, "All these references base their discussion of the Bohr–van Leeuwen theorem on Niels Bohr's physical model, in which perfectly reflecting walls are necessary to provide the currents that cancel the net contribution from the interior of an element of plasma, and result in zero net diamagnetism for the plasma element." Diamagnetism of a purely classical nature occurs in plasmas but is a consequence of thermal disequilibrium, such as a gradient in plasma density. Electromechanics and electrical engineering also see practical benefit from the Bohr–van Leeuwen theorem.
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Abrikosov was born in Moscow, Russian SFSR, Soviet Union, on June 25, 1928, to a couple of physicians: Prof. Alexei Ivanovich Abrikosov and Dr. Fani Abrikosova, née Wulf, a Jewish Russian physician. He graduated from Moscow State University in 1948. From 1948 to 1965, he worked at the Institute for Physical Problems of the USSR Academy of Sciences, where he received his Ph.D. in 1951 for the theory of thermal diffusion in plasmas, and then his Doctor of Physical and Mathematical Sciences (a "higher doctorate") degree in 1955 for a thesis on quantum electrodynamics at high energies.
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At present, there is no single equation of state that accurately predicts the properties of all substances under all conditions. An example of an equation of state correlates densities of gases and liquids to temperatures and pressures, known as the ideal gas law, which is roughly accurate for weakly polar gases at low pressures and moderate temperatures. This equation becomes increasingly inaccurate at higher pressures and lower temperatures, and fails to predict condensation from a gas to a liquid. Another common use is in modeling the interior of stars, including neutron stars, dense matter (quark–gluon plasmas) and radiation fields.
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Mima is a Fellow of the American Physical Society and a Member of the Physical Society of Japan and the Japan Society of Plasma Science at Nuclear Fusion Research. He was a co- recipient of the 1993 John Dawson Award for Excellence in Plasma Physics Research and won the 2007 Edward Teller Award. He was jointly awarded the 2011 Hannes Alfvén Prize (with Akira Hasegawa and Patrick H. Diamond) for "laying the foundations of modern numerical transport simulations and key contributions on self-generated zonal flows and flow shear decorrelation mechanisms which form the basis of modern turbulence in plasmas".
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The stellarator was invented by American scientist Lyman Spitzer of Princeton University in 1951, and much of its early development was carried out by his team at what became the Princeton Plasma Physics Laboratory (PPPL). Lyman's Model A began operation in 1953 and demonstrated plasma confinement. Larger models followed, but these demonstrated poor performance, suffering from a problem known as pump-out that caused them to lose plasma at rates far worse than theoretical predictions. By the early 1960s, any hope of quickly producing a commercial machine faded, and attention turned to studying the fundamental theory of high-energy plasmas.
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While working at Los Alamos in 1950, John Wheeler suggested setting up a secret research lab at Princeton University that would carry on theoretical work on H-bombs after he returned to the university in 1951. Spitzer was invited to join this program, given his previous research in interstellar plasmas. But by the time of his trip to Aspen, Spitzer had lost interest in bomb design and he turned his attention full-time to fusion as a power source. Over the next few months, Spitzer produced a series of reports outlining the conceptual basis for the stellarator, as well as potential problems.
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A spheromak is an arrangement of plasma formed into a toroidal shape similar to a smoke ring.Arnie Heller, "Experiment Mimics Nature's Way with Plasmas", Lawrence Livermore National Laboratory The spheromak contains large internal electric currents and their associated magnetic fields arranged so the magnetohydrodynamic forces within the spheromak are nearly balanced, resulting in long-lived (microsecond) confinement times without external fields. Spheromaks belong to a type of plasma configuration referred to as the compact toroids. The physics of the spheromak and of collisions between spheromaks is similar to a variety of astrophysical events, like coronal loops and filaments, relativistic jets and plasmoids.
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Spitzer ascribed the difference between the Bohm and classical diffusion rates to turbulence in the plasma, and believed the steady fields of the stellarator would not suffer from this problem. Various experiments at that time suggested the Bohm rate did not apply, and that the classical formula was correct. But by the early 1960s, with all of the various designs leaking plasma at a prodigious rate, Spitzer himself concluded that the Bohm scaling was an inherent quality of plasmas, and that magnetic confinement would not work. The entire field descended into what became known as "the doldrums", a period of intense pessimism.
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While the tokamak addresses the issue of plasma stability in a gross sense, plasmas are also subject to a number of dynamic instabilities. One of these, the kink instability, is strongly suppressed by the tokamak layout, a side-effect of the high safety factors of tokamaks. The lack of kinks allowed the tokamak to operate at much higher temperatures than previous machines, and this allowed a host of new phenomena to appear. One of these, the banana orbits, is caused by the wide range of particle energies in a tokamak – much of the fuel is hot but a certain percentage is much cooler.
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The technique has also been used to fix the positron density before the positrons and antiprotons are combined. Recently it was discovered that one could set all of the important parameters of the electron and positron plasmas for antihydrogen production using the RW to fix the plasma density and evaporative cooling to cool the plasma and fix the on-axis space charge potential. The result was greatly increased reproducibility for antihydrogen production. In particular, this technique, dubbed SDREVC (strong drive regime evaporative cooling), was successful to the extent that it increased the number of trappable antihydrogen by an order of magnitude.
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After his PhD, he worked at the Princeton Plasma Physics Laboratory (on "Project Matterhorn"), where he was one of the leading theoretical physicists and remained until 1982. In 1982 he was Senior Technical Advisor in the theory group of General Atomics and simultaneously adjunct professor at the University of California, San Diego. He was the author of a series of works with John Johnson and Katherine Weimer on equilibria and instabilities in Tokamak and Stellarator plasmas in magnetohydrodynamics. With Johnson and Ray Grimm he developed the computer program PEST (Princeton Equilibrium and Stability in Tokamak's Code).
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This research was undertaken on the Mega Ampere Spherical Tokamak (MAST) at Culham Centre for Fusion Energy. Melanie showed that MAST plasmas may be more unstable to vertical disruptions than other tokamaks due to a combination of the magnetic field structure and the lack of a close-fitting wall.Non-linear instability at large vertical displacements in the MAST tokamak, M.J. Windridge, G. Cunningham, T.C. Hender, R. Khayrutdinov, V.E. Lukash, Plasma Physics and Controlled Fusion, 53 (2011) 035018 Following her PhD, Windridge was chosen as the Institute of Physics Schools and Colleges Lecturer for 2010, which launched her science communication career.Wade, Andrew.
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Ideal MHD instabilities driven by current or pressure gradients represent the ultimate operational limit for most configurations. The long-wavelength kink mode and short-wavelength ballooning mode limits are generally well understood and can in principle be avoided. Intermediate-wavelength modes (n ~ 5-10 modes encountered in tokamak edge plasmas, for example) are less well understood due to the computationally intensive nature of the stability calculations. The extensive beta limit database for tokamaks is consistent with ideal MHD stability limits, yielding agreement to within about 10% in beta for cases where the internal profiles of the plasma are accurately measured.
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If the system has no magnetic or electrostatic asymmetries in the plane perpendicular to B, there are no torques on the plasma; thus L_z is constant, and the plasma cannot expand. As discussed below, these plasmas do expand due to magnetic and/or electrostatic asymmetries thought to be due to imperfections in trap construction. The PM traps are typically filled using sources of low energy charged particles. In the case of electrons, this can be done using a hot filament or electron gun. For positrons, a sealed radioisotope source and “moderator” (the latter used to slow the positrons to electron-volt energies) can be used.
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Explorer 18 was a solar cell and chemical-battery powered spacecraft instrumented for interplanetary and distant magnetospheric studies of energetic particles, cosmic rays, magnetic fields, and plasmas. Initial spacecraft parameters included a local time of apogee of 1020 hours, a spin rate of 22 rpm, and a spin direction of 115° right ascension and -25° declination. Each normal telemetry sequence of 81.9 s duration consisted of 795 data bits. After every third normal sequence there was an 81.9-s interval of rubidium vapor magnetometer analog data transmission. The spacecraft performed normally until May 30, 1964, then intermittently until May 10, 1965, when it was abandoned.
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Winterberg has published numerous articles in the area of inertial confinement fusion. In particular, Winterberg is known for the idea of impact fusion and the concept of the magnetically insulated diode for the generation of multi-megampere megavolt ion beams for the purpose of heating plasmas to thermonuclear fusion temperatures. He conceived of a nuclear fusion propulsion reactor for space travel, which is called the Winterberg / Daedalus ClassM. W. Turner, C. W. Hawk, R. J. Litchford, Experiments in Magnetic Flux Compression using Plasma Armatures, 12th Annual NASA/JPL/MSFC Advanced Space Propulsion Workshop Magnetic Compression Reaction Chamber, which was later developed at the University of Alabama at Huntsville's Propulsion Research Center.
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Fig. 1. The surface of a MEMS device is cleaned with bright, blue oxygen plasma in a plasma etcher to rid it of carbon contaminants. (100mTorr, 50W RF) Plasma cleaning is the removal of impurities and contaminants from surfaces through the use of an energetic plasma or dielectric barrier discharge (DBD) plasma created from gaseous species. Gases such as argon and oxygen, as well as mixtures such as air and hydrogen/nitrogen are used. The plasma is created by using high frequency voltages (typically kHz to >MHz) to ionise the low pressure gas (typically around 1/1000 atmospheric pressure), although atmospheric pressure plasmas are now also common.
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VSim is a cross-platform (Windows, Linux, and macOS) computational framework for multiphysics, including electrodynamics in the presence of metallic and dielectric shapes as well as with or without self-consistent charged particles and fluids. VSim comes with VSimComposer, a full-featured graphical user interface for visual setup of any simulation, including CAD geometry import and/or direct geometry construction. With VSimComposer, the user can execute data analysis scripts and visualize results in one, two, or three dimensions. VSim computes using the powerful Vorpal computational engine, which has been used to simulate the dynamics of electromagnetic systems, plasmas, and rarefied as well as dense gases.
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The ability to control the etching direction and speed with an applied voltage or electrode configuration, as with electrochemical machining, gives additional capabilities not available with isotropic chemical-only approaches. Dry processing methods such as hot oxygen or plasmas can also burn off the graphite faster than the diamond, as can a simple acetylene torch. These require higher temperatures and do not have the same high selectivity that can be achieved with the electrochemical approach. Surface termination is often an issue with both solid state and vacuum devices, and the details of final surface band structure have been compared with alternatives in various device structures.
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For example, the plasma itself emits EM radiation, although it is usually weak and noise-like in spectrum. Also, it takes some time for plasma to be re- absorbed by the atmosphere and a trail of ionized air would be created behind the moving aircraft, but at present there is no method to detect this kind of plasma trail at long distance. Thirdly, plasmas (like glow discharges or fluorescent lights) tend to emit a visible glow: this is not compatible with overall low observability concept. However, present optical detection devices like FLIR has a shorter range than radar, so Plasma Stealth still has an operational range space.
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This region of "space weather" is the site of geomagnetic storms that disrupt communications systems and pose radiation hazards to humans traveling in airplanes (if both altitude and latitude are high) or in orbiting spacecraft. A deeper understanding of this region is vitally important. Geomagnetic weather systems have been late to benefit from the satellite imagery taken for granted in weather forecasting, and space physics because their origins in magnetospheric plasmas present the added problem of invisibility. The heliosphere protects the entire Solar System from the majority of cosmic rays but is so remote that only an imaging technique such as ENA imaging will reveal its properties.
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Kennedy J. Reed is an American theoretical atomic physicist in the Theory Group in the Physics & Advanced Technologies Directorate at Lawrence Livermore National Laboratory (LLNL) and a founder of the National Physical Science Consortium (NPSC), a group of about 30 universities that provides physics fellowships for women and minorities.Distinguished African American Scientists of the Twentieth Century, James H. Kessler, Greenwood Publishing Group, 1996. Reed earned his Ph.D. at the University of Nebraska, was a professor of physics at Morehouse College, in Atlanta, Georgia and is known for his work related to ionization and atomic collisions in high temperature plasmas. He has published more than 100 papers.
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Photo Ruth Garita, OCM-TEC. The government of Costa Rica awarded Vargas-Blanco with the Clodomiro Picado Twight National Prize for Science and Technology on November 30, of that most remarkable year. The newspaper La Nación from Costa Rica chose Vargas-Blanco as one of the "New Person of the Year" published in the December 2016 edition of their Sunday Magazine. On November 27, 2017, Vargas-Blanco was chosen by the IAEA as one of their twenty eight scientists/representatives worldwide making him the only Latin American member of the Fusion Energy Conference Program Committee, the world's most important conference on plasmas for nuclear fusion sponsored by the IAEA.
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The cascaded arc source, developed at the Eindhoven University of Technology, G.M.W. Kroesen, D.C. Schram, and J.C.M. de Haas, Plasma Chemistry and Plasma Processing, 10(4):531–551, 1990. M.C.M. van de Sanden, G.J.H. Brussaard, W.M.M. Kessels, A. de Graaf, M.F.A.M. van Hest, K.G.Y. Letourneur and D.C. Schram is shown in the figure below. Compared to plasma sources in other linear plasma generators, this source can produce high- density argon and hydrogen plasmas (respectively 1021 – 1024 and 1019 – 1022 m−3) at a relatively low electron temperature (~1 eV). Due to the high collision frequency of the particles in the source, the plasma is in thermal equilibrium and reasonably homogeneous.
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In most cases the electrons are close enough to thermal equilibrium that their temperature is relatively well-defined; this is true even when there is a significant deviation from a Maxwellian energy distribution function, for example, due to UV radiation, energetic particles, or strong electric fields. Because of the large difference in mass, the electrons come to thermodynamic equilibrium amongst themselves much faster than they come into equilibrium with the ions or neutral atoms. For this reason, the ion temperature may be very different from (usually lower than) the electron temperature. This is especially common in weakly ionized technological plasmas, where the ions are often near the ambient temperature.
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If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to what is termed a Debye sheath. The good electrical conductivity of plasmas makes their electric fields very small. This results in the important concept of "quasineutrality", which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma (n_e = \langle Z\rangle n_i), but on the scale of the Debye length there can be charge imbalance. In the special case that double layers are formed, the charge separation can extend some tens of Debye lengths.
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Although the underlying equations governing plasmas are relatively simple, plasma behaviour is extraordinarily varied and subtle: the emergence of unexpected behaviour from a simple model is a typical feature of a complex system. Such systems lie in some sense on the boundary between ordered and disordered behaviour and cannot typically be described either by simple, smooth, mathematical functions, or by pure randomness. The spontaneous formation of interesting spatial features on a wide range of length scales is one manifestation of plasma complexity. The features are interesting, for example, because they are very sharp, spatially intermittent (the distance between features is much larger than the features themselves), or have a fractal form.
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Dynamos make use of this basic process ("the dynamo effect"), any and all conductors, solid or otherwise are so affected, including plasmas and other fluids. The IMF originates on the Sun, linked to the sunspots, and its field lines (lines of force) are dragged out by the solar wind. That alone would tend to line them up in the Sun-Earth direction, but the rotation of the Sun angles them at Earth by about 45 degrees forming a spiral in the ecliptic plane), known as the Parker spiral. The field lines passing Earth are therefore usually linked to those near the western edge ("limb") of the visible Sun at any time.Alaska.
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Theoretical studies and experiments were made to augment the data comparisons and evaluations; such studies embraced the computational areas of numerical, mathematical, and statistical analysis, analog and digital simulation, and computer programming as well as the many physical sciences associated with missile flight and atmospheric re-entry. One of the most important facets of re-entry physics is the interaction of plasmas and ionized wakes with electromagnetic waves. Work was being conducted in both the theoretical and practical nature of plasma physics as related to radar and associated phenomena; the following subcontract organization and consultants were active in support of phases of this research: # RCA Victor, Ltd. Research Laboratories, Montreal, Canada.
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It is more common to excite a capacitive discharge by applying an AC or RF signal between an electrode and the conductive walls of a reactor chamber, or between two cylindrical conductive electrodes facing one another. The latter configuration is known as a parallel plate reactor. Frequencies of a few tens of Hz to a few thousand Hz will produce time-varying plasmas that are repeatedly initiated and extinguished; frequencies of tens of kilohertz to tens of megahertz result in reasonably time-independent discharges. Excitation frequencies in the low-frequency (LF) range, usually around 100 kHz, require several hundred volts to sustain the discharge.
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These large voltages lead to high-energy ion bombardment of surfaces. High-frequency plasmas are often excited at the standard 13.56 MHz frequency widely available for industrial use; at high frequencies, the displacement current from sheath movement and scattering from the sheath assist in ionization, and thus lower voltages are sufficient to achieve higher plasma densities. Thus one can adjust the chemistry and ion bombardment in the deposition by changing the frequency of excitation, or by using a mixture of low- and high-frequency signals in a dual-frequency reactor. Excitation power of tens to hundreds of watts is typical for an electrode with a diameter of 200 to 300 mm.
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The current laser at the UK Atomic Weapons Establishment (AWE), the HELEN (High Energy Laser Embodying Neodymium) 1-terawatt neodymium-glass laser, can access the midpoints of pressure and temperature regions and is used to acquire data for modeling on how density, temperature, and pressure interact inside warheads. HELEN can create plasmas of around 106 K, from which opacity and transmission of radiation are measured. Neodymium glass solid-state lasers are used in extremely high power (terawatt scale), high energy (megajoules) multiple beam systems for inertial confinement fusion. Nd:glass lasers are usually frequency tripled to the third harmonic at 351 nm in laser fusion devices.
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In the United States and Europe, solid state became a prominent field through its investigations into semiconductors, superconductivity, nuclear magnetic resonance, and diverse other phenomena. During the early Cold War, research in solid state physics was often not restricted to solids, which led some physicists in the 1970s and 1980s to found the field of condensed matter physics, which organized around common techniques used to investigate solids, liquids, plasmas, and other complex matter. Today, solid-state physics is broadly considered to be the subfield of condensed matter physics, often referred to as hard condensed matter, that focuses on the properties of solids with regular crystal lattices.
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In 1997, scientists at the Joint European Torus (JET) facilities in the UK produced 16 megawatts of fusion power. Scientists can now exercise a measure of control over plasma turbulence and resultant energy leakage, long considered an unavoidable and intractable feature of plasmas. There is increased optimism that the plasma pressure above which the plasma disassembles can now be made large enough to sustain a fusion reaction rate acceptable for a power plant. Electromagnetic waves can be injected and steered to manipulate the paths of plasma particles and then to produce the large electrical currents necessary to produce the magnetic fields to confine the plasma.
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Hannes Olof Gösta Alfvén (; 30 May 1908 – 2 April 1995) was a Swedish electrical engineer, plasma physicist and winner of the 1970 Nobel Prize in Physics for his work on magnetohydrodynamics (MHD). He described the class of MHD waves now known as Alfvén waves. He was originally trained as an electrical power engineer and later moved to research and teaching in the fields of plasma physics and electrical engineering. Alfvén made many contributions to plasma physics, including theories describing the behavior of aurorae, the Van Allen radiation belts, the effect of magnetic storms on the Earth's magnetic field, the terrestrial magnetosphere, and the dynamics of plasmas in the Milky Way galaxy.
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Ignitor is part of the line of research on high magnetic field, experiments producing high density plasmas that began with the Alcator and the Frascati Torus programs at MIT and in Italy, respectively. It remains, at the world level, the only experiment capable of reaching ignition by the magnetic field confinement approach. However, several fusion scientists have contested the claim made for IGNITOR that it is a bigger step towards fusion power than the international ITER project. According to existing plans, Ignitor will be installed at the Triniti site at Troitsk near Moscow that has facilities which can be upgraded to house and operate the machine.
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Even the most powerful flares are barely detectable in the total solar irradiance (the "solar constant"). Solar flares occur in a power-law spectrum of magnitudes; an energy release of typically 1020 joules of energy suffices to produce a clearly observable event, while a major event can emit up to 1025 joules. Flares are closely associated with the ejection of plasmas and particles through the Sun's corona into outer space; flares also copiously emit radio waves. If the ejection is in the direction of the Earth, particles associated with this disturbance can penetrate into the upper atmosphere (the ionosphere) and cause bright auroras, and may even disrupt long range radio communication.
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In 1997, he received the from the Société Française de Physique. In 2014, he received the Hannes Alfvén Prize from the European Physical Society for "decisive results in the field of laser-produced plasma physics, in particular for illuminating descriptions of laser light absorption in plasmas, electron heat transport in steep temperature gradients and plasma expansion dynamics into vacuum". In 2019, he received the Edward Teller Award from the American Nuclear Society for "his scientific contributions to laser-plasma physics, from laser from laser light absorption to non-local electron heat transport and plasma expansion dynamics, and for his inspiring spirit of community service".
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Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them. It has applications in a wide range of disciplines, including mechanical, civil, chemical and biomedical engineering, geophysics, oceanography, meteorology, astrophysics, and biology. It can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion. It is a branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms; that is, it models matter from a macroscopic viewpoint rather than from microscopic.
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At McGill he became a research associate and then an assistant professor, leaving in 1957 to join MIT's Plasma Physics Group in the Research Laboratory of Electronics. Bekefi remained at MIT for the remainder of his career. In MIT's physics department he became in 1961 an assistant professor, in 1964 an associate professor, and in 1967 a full professor, retiring in the summer of 1995 as professor emeritus. (NOTE: The preceding quotation from the New York Times obituary should have "author or co-author" instead of "co-author" because Bekefi was the sole author of Radiation Processes in Plasmas.) Bekefi guided about 50 graduate students to their M.S. and Ph.D. degrees.
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Shiva was never expected to reach ignition conditions, and was primarily intended as a proof-of-concept system for a larger device that would. Even before Shiva was completed, the design of this successor, then known as Shiva/Nova, was well advanced. Shiva/Nova would emerge as Nova in 1984. Shiva was heavily instrumented, and its target chamber utilized high-resolution, high-speed optical and X-ray instruments for the characterization of the plasmas created during implosion. When experiments with targets started in Shiva in 1978, compression was ramped upward to about 50 to 100 times the original density of the liquid hydrogen, or about 3.5 to 7 g/mL.
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This magnetic confinement prevents the uncontrolled expansion of the electrons in the radial direction and guides them axially downstream. The heavier ions are typically unmagnetized or only partially magnetized, but are forced to expand with the electrons thanks to the electric field that is set up in the plasma to maintain quasineutrality.E. Ahedo, M. Merino, Two-dimensional supersonic plasma acceleration in a magnetic nozzle, Physics of Plasmas 17, 073501 (2010) As a result of the ensuing electric field, the ions are accelerated downstream, while all electrons except the more energetic ones are confined upstream. In this way, the electric field helps convert the electron internal energy into directed ion kinetic energy.
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When the topic of controlled fusion was first being studied, it was believed that the plasmas would follow the classical diffusion rate, and this suggested that useful confinement times would be relatively easy to achieve. However, in 1949 a team studying plasma arcs as a method of isotope separation found that the diffusion time was much greater than what was predicted by the classical method. David Bohm suggested it scaled with B. If this is true, Bohm diffusion would mean that useful confinement times would require impossibly large fields. In practice, machines have demonstrated a wide array of diffusion rates between these two extremes.
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Kivelson has had a very successful career as a scientist that include many publications and original work. Some of her accomplishments are discovering an internal magnetic field at Ganymede, providing compelling evidence for a sub-surface ocean at Europa, and elucidating some of the processes explaining the behavior of ultralow frequency waves in the terrestrial magnetosphere, the discovery of cavity mode oscillations in the magnetosphere, developed new ways of describing wave-particle interactions in magnetohydrodynamic waves, and provided insight into the mechanism of interchange diffusion in rotating plasmas. This research has led Kivelson to being an author or co-author on over 350 publications that have accumulated over 12,000 citations.
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MHD converters involving plasmas were highly studied in the 1960s and 1970s, with many government funding and dedicated international conferences. One major conceptual application was the use of MHD converters on the hot exhaust gas in a coal fired power plant, where it could extract some of the energy with very high efficiency, and then pass it into a conventional steam turbine. The research almost stopped after it was considered the electrothermal instability would severely limit the efficiency of such converters when intense magnetic fields are used, although solutions may exist. center Crossed-field magnetohydrodynamic converters (linear Faraday type with segmented electrodes) A: MHD generator.
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The mechanical dynamo, in contrast, uses the motion of mechanical devices to accomplish this. Practical MHD generators have been developed for fossil fuels, but these were overtaken by less expensive combined cycles in which the exhaust of a gas turbine or molten carbonate fuel cell heats steam to power a steam turbine. MHD dynamos are the complement of MHD accelerators, which have been applied to pump liquid metals, seawater and plasmas. Natural MHD dynamos are an active area of research in plasma physics and are of great interest to the geophysics and astrophysics communities, since the magnetic fields of the earth and sun are produced by these natural dynamos.
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Hannes Alfvén suggested that scaling laboratory results can be extrapolated up to the scale of the universe. A scaling jump by a factor 109 was required to extrapolate to the magnetosphere, a second jump to extrapolate to galactic conditions, and a third jump to extrapolate to the Hubble distance. Plasma cosmology is a non-standard cosmology whose central postulate is that the dynamics of ionized gases and plasmas play important, if not dominant, roles in the physics of the universe beyond the Solar System. recount: It was described as this in the February 1992 issue of Sky & Telescope ("Plasma Cosmology"), and by Anthony Peratt in the 1980s, who describes it as a "nonstandard picture".
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Due to the obvious military applications of the subject, there are few readily available experimental studies of plasma's effect on the radar cross section (RCS) of aircraft, but plasma interaction with microwaves is a well explored area of general plasma physics. Standard plasma physics reference texts are a good starting point and usually spend some time discussing wave propagation in plasmas. One of the most interesting articles related to the effect of plasma on the RCS of aircraft was published in 1963 by the IEEE. The article is entitled "Radar cross sections of dielectric or plasma coated conducting spheres and circular cylinders" (IEEE Transactions on Antennas and Propagation, September 1963, pp. 558-569).
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S. Atzeni, et al., "Fast ignitor target studies for the HiPER project" , Physics of Plasmas, Vol. 15, 056311 (2008), When the amplification process is complete the laser light enters the experimental chamber, lying at one end of the building. Here it is reflected off a series of deformable mirrors that help correct remaining imperfections in the wavefront, and then feeds them into the target chamber from all angles. Since the overall distances from the ends of the beamlines to different points on the target chamber are different, delays are introduced on the individual paths to ensure they all reach the center of the chamber at the same time, within about 10 picoseconds (ps).
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Typical flaring coronal loops observed by TRACE in the EUV rays Telescopic observations suggest that the solar magnetic field, which theoretically is "frozen" into the gas of the plasma in the photosphere, expands into roughly semicircular structures in the corona. These coronal loops, which can be seen in the EUV and X-ray images (see the figure on the left), often confine very hot plasmas, with emissions characteristic of temperature of a one to a few million degrees. Many flux tubes are relatively stable as seen in soft X-ray images, emitting at steady rate. However flickerings, brightenings, small explosions, bright points, flares and mass eruptions are observed very frequently, especially in active regions.
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Additionally, the equation appears in the studies of small-amplitude gravity waves on the surface of deep inviscid (zero-viscosity) water; the Langmuir waves in hot plasmas; the propagation of plane-diffracted wave beams in the focusing regions of the ionosphere; the propagation of Davydov's alpha-helix solitons, which are responsible for energy transport along molecular chains; and many others. More generally, the NLSE appears as one of universal equations that describe the evolution of slowly varying packets of quasi-monochromatic waves in weakly nonlinear media that have dispersion. Unlike the linear Schrödinger equation, the NLSE never describes the time evolution of a quantum state. The 1D NLSE is an example of an integrable model.
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The Shkarofsky function is a physics formula which describes the behavior of microwaves. It is named after Canadian physicist Issie Shkarofsky (1931-2018), who first identified the function in 1966.I.P. Shkarofsky, "Dielectric Tensor in Vlasov Plasmas near Cyclotron Harmonics" in Physic of Fluids 9, 561 (1966) N.M. Temme and S.S. Sazhin later developed this idea further to give what they called the generalized Shkarofsky function.Sazhin and Temme, "Relativistic Effects on Parallel Whistler-Mode Propagation and Instability" in Astrophysics and Space Science, April 1990, Volume 166, Issue 2, pp 301-313Temme, Sumner and Sazhin, "Analytical and Numberical Analysis of the Generalized Shkarofsky Function" in Astrophysics and Space Science, August 1992, Vol 194, Issue 2, pp 173-196.
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This section discusses the plasma physics theory that explains passive current collection to a large conductive body which will be applied at the end of an ED tether. When the size of the sheath is much smaller than the radius of the collecting body then depending on the polarity of the difference between the potential of the tether and that of the ambient plasma, (V – Vp), it is assumed that all of the incoming electrons or ions that enter the plasma sheath are collected by the conductive body. This 'thin sheath' theory involving non-flowing plasmas is discussed, and then the modifications to this theory for flowing plasma is presented. Other current collection mechanisms will then be discussed.
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However, because phenomenologically is the inverse effect of the magneto-optical Faraday effect, magnetization reversal by circularly polarized light is referred to as the inverse Faraday effect. Early studies in plasmas, paramagnetic solids, dielectric magnetic materials and ferromagnetic semiconductors demonstrated that excitation of a medium with a circularly polarized laser pulse corresponds to the action of an effective magnetic field. Yet, before the experiments of Stanciu and Hansteen, all- optical controllable magnetization reversal in a stable magnetic state was considered impossible. In quantum field theory and quantum chemistry the effect where the angular momentum associated to the circular motion of the photons induces an angular momentum in the electrons is called photomagneton.
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He has worked on high-energy-density plasmas and related phenomena, intense particle beams and intense microwave sources, explosively-driven pulsed-power generators, the z-pinch effect, and nuclear fusion target designs. He is an influential proponent of plasma cosmology, a non-standard cosmology proposed as an alternative to the Big Bang and rejected by mainstream cosmologists. He wrote a book on the subject, was guest editor for the space plasma special editions at the IEEE journal Transactions on Plasma Science devoted primarily to plasma cosmology, and wrote some papers on the subject. He has researched petroglyphs, some of which he claims are records made in prehistory about significant auroral events caused by intense solar storms.
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Among his achievements are a partially phenomenological theory of superconductivity, the Ginzburg–Landau theory, developed with Lev Landau in 1950; the theory of electromagnetic wave propagation in plasmas (for example, in the ionosphere); and a theory of the origin of cosmic radiation. He is also known to biologists as being part of the group of scientists that helped bring down the reign of the politically connected anti-Mendelian agronomist Trofim Lysenko, thus allowing modern genetic science to return to the USSR. In 1937, Ginzburg married Olga Zamsha. In 1946, he married his second wife, Nina Ginzburg (nee Yermakova), who had spent more than a year in custody on fabricated charges of plotting to assassinate the Soviet leader Joseph Stalin.
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Neutral beam injection (NBI) is one method used to heat plasma inside a fusion device consisting in a beam of high-energy neutral particles that can enter the magnetic confinement field. When these neutral particles are ionized by collision with the plasma particles, they are kept in the plasma by the confining magnetic field, and can transfer most of their energy by further collisions with the plasma. By tangential injection in the torus, neutral beams also provide momentum to the plasma and current drive, one essential feature for long pulses of burning plasmas. Neutral beam injection is a flexible and reliable technique, which has been the main heating system on a large variety of fusion devices.
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J., 585, 1169. 2000, "New Population of Galactic High Energy Gamma Ray Sources", N. Gehrels, D. Macomb, D. Bertsch, D. Thompson,& R. Hartman, Nature, 404, 363. 1999, "Revisiting the Black Hole", R. Blandford & N. Gehrels, Physics Today, June 1999 p. 40\. 1998, "The New Gamma Ray Astronomy", N. Gehrels and J. Paul, Physics Today, February 1998 issue, p. 26\. 1995, "Two Classes of Gamma-Ray Emitting Active Galactic Nuclei", C. Dermer & N. Gehrels, Astrophys. J., 447, 103. 1993, "The Geminga Supernova as a Possible Cause of the Local Interstellar Bubble", N. Gehrels & W. Chen, Nature 361, 706. 1993, "Temperatures of Enhanced Stability in Hot Thin Plasmas", N. Gehrels & E. D. Williams, ApJ, 418, L25.
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Gamma Cassiopeiae is the prototype of a small group of stellar sources of X-ray radiation that is about 10 times stronger than emitted from other B or Be stars. The character of the X-ray spectrum is Be thermal, possibly emitted from plasmas of temperatures up to least ten million kelvins, and shows very short term and long-term cycles. Historically, it has been held that these X-rays might be excited by matter originating from the star, from a hot wind or a disk around the star, accreting onto the surface of a degenerate companion, such as a white dwarf or neutron star. However, there are difficulties with either of these hypotheses.
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A solution used on most tokamak designs is the limiter, a small ring of light metal that projected into the chamber so that the plasma would hit it before hitting the walls. This eroded the limiter and caused its atoms to mix with the fuel, but these lighter materials cause less disruption than the wall materials. When reactors moved to the D-shaped plasmas it was quickly noted that the escaping particle flux of the plasma could be shaped as well. Over time, this led to the idea of using the fields to create an internal divertor that flings the heavier elements out of fuel, typically towards the bottom of the reactor.
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This did not result in McDonald losing ONR funding but did draw some criticism of Klass from members of the UFO community. Criticism was also expressed by a more skeptical team of plasma experts assembled by the Condon Committee, all of whom rejected Klass's plasma theory as unscientific. Since that time, theories evoking similar phenomena with widely differing modes of generation have been proposed by commentators such as Michael Persinger, Terence Meaden, Albert Budden, and Paul Devereux. In 1999 the MoD Project Condign report proposed that "Unidentified Aerial Phenomena" (UAPs) comparable to the plasmas originally advocated by Klass (but as amended by Devereux and Randles) may represent a viable explanation for some UFO events.
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In 1955, Ohkawa independently came up with idea of the fixed- field alternating gradient accelerator (FFAG) together with Keith Symon and Andrei Kolomensky, which led to the development of the first prototype in 1956 by the Midwestern Universities Research Association (MURA). He then developed a procedure to stabilize instabilities in tokamaks using multipole magnetic fields with Donald Kerst in 1960, which was then later confirmed by experiments. In 1968, Ohkawa demonstrated that the plasma-current multipole configuration used to trap plasmas was stable, which resulted in the development of a series of tokamaks with vertically elongated plasma cross sections called the doublet. This eventually led to General Atomics' DIII-D tokamak, which influenced the design and concept of ITER.
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In plasma enhanced CVD (PECVD) processes, DC electric fields, radio-frequency electric fields, or microwaves produce plasmas to primarily lower the synthesis temperature of CNTs. At the same time, an electric field (DC or AC) is also produced over the substrate surface to direct CNT growth propagation. The DC-PECVD process for vertically aligned CNT arrays includes four basic steps: evacuation, heating, plasma generation, and cooling. A typical procedure is conducted at a pressure of 8 Torr in NH3 and at a growth temperature in the range of 450–600 ◦. As soon as the temperature and pressure are stabilized, a DC bias voltage of 450–650 V is applied to the gap between two electrodes to ignite an electrical discharge (plasma) over the sample.
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A bare proton, , cannot exist in solution or in ionic crystals because of its unstoppable attraction to other atoms or molecules with electrons. Except at the high temperatures associated with plasmas, such protons cannot be removed from the electron clouds of atoms and molecules, and will remain attached to them. However, the term 'proton' is sometimes used loosely and metaphorically to refer to positively charged or cationic hydrogen attached to other species in this fashion, and as such is denoted "" without any implication that any single protons exist freely as a species. To avoid the implication of the naked "solvated proton" in solution, acidic aqueous solutions are sometimes considered to contain a less unlikely fictitious species, termed the "hydronium ion" ().
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A ball-pen probe is a modified Langmuir probe used to measure the plasma potential in magnetized plasmas. The ball-pen probe balances the electron and ion saturation currents, so that its floating potential is equal to the plasma potential. Because electrons have a much smaller gyroradius than ions, a moving ceramic shield can be used to screen off an adjustable part of the electron current from the probe collector. Ball-pen probes are used in plasma physics, notably in tokamaks such as CASTOR, (Czech Academy of Sciences Torus) ASDEX Upgrade, COMPASS, ISTTOK, MAST, TJ-K, RFX, H-1 Heliac, IR-T1, GOLEM as well as low temperature devices as DC cylindrical magnetron in Prague and linear magnetized plasma devices in Nancy and Ljubljana.
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However, it has been questioned in a series of journal articles whether the quantum mechanically canonised London equations can be given a purely classical derivation. Bostick, for instance, has claimed to show that the London equations do indeed have a classical origin that applies to superconductors and to some collisionless plasmas as well. In particular it has been asserted that the Beltrami vortices in the plasma focus display the same paired flux-tube morphology as Type II superconductors. Others have also pointed out this connection, Fröhlich has shown that the hydrodynamic equations of compressible fluids, together with the London equations, lead to a macroscopic parameter (\mu = electric charge density / mass density), without involving either quantum phase factors or Planck's constant.
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A fusion torch is a technique for utilizing the high-temperature plasma of a fusion reactor to break apart other materials (especially waste materials) and convert them into a few reusable and saleable elements. It was invented in 1968 by Bernard J. Eastlund and William C. Gough while they were program managers of the controlled thermonuclear research program of the United States Atomic Energy Commission (AEC). The basic concept was to impinge the plasma leaking from fusion reactors onto solids or liquids, vaporizing, dissociating and ionizing the materials, then separating the resulting elements into separate bins for collection. Other applications of fusion plasmas such as generation of UV and optical light, and generation of hydrogen fuel, were also described in their associated 1969 paper.
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In these plasmas the positive ions are almost all singly charged and there are few negative ions, so there are nearly equal amounts of ions and electrons in each unit volume of plasma. What makes Inductively Coupled Plasma Mass Spectrometry (ICP-MS) unique to other forms of inorganic mass spectrometry is its ability to sample the analyte continuously, without interruption. This is in contrast to other forms of inorganic mass spectrometry; Glow Discharge Mass Spectrometry (GDMS) and Thermal Ionization Mass Spectrometry (TIMS), that require a two-stage process: Insert sample(s) into a vacuum chamber, seal the vacuum chamber, pump down the vacuum, energize sample, thereby sending ions into the mass analyzer. With ICP-MS the sample to be analyzed is sitting at atmospheric pressure.
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K. U. Gross and R. M. Dreizler, Density Functional Theory, Plenum 1993 and even used in quantum theories of plasmas. In 2004, a study of all citations to the Physical Review journals from 1893 until 2003, found Kohn to be an author of five of the 100 papers with the "highest citation impact", including the first two.Redner, S. Citation Statistics From More Than a Century of Physical Review 2004 Walter Kohn receiving an honorary doctorate at The University of Oxford In 1957, he relinquished his Canadian citizenship and became a naturalized citizen of the United States. In 1963 Kohn became a Member of the American Academy of Arts and Sciences and in 1969, a Member of the National Academy of Sciences.
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Space physics, also known as solar-terrestrial physics, is the study of plasmas as they occur naturally in the Earth's upper atmosphere (aeronomy) and within the Solar System. As such, it encompasses a far-ranging number of topics, such as heliophysics which includes the solar physics of the Sun: the solar wind, planetary magnetospheres and ionospheres, auroras, cosmic rays, and synchrotron radiation. Space physics is a fundamental part of the study of space weather and has important implications in not only to understanding the universe, but also for practical everyday life, including the operations of communications and weather satellites. Space physics is distinct from astrophysical plasma and the field of astrophysics, which studies similar plasma phenomena beyond the Solar System.
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Polarizational bremsstrahlung (sometimes referred to as "atomic bremsstrahlung") is the radiation emitted by the target's atomic electrons as the target atom is polarized by the Coulomb field of the incident charged particle.Polarization Bremsstrahlung on Atoms, Plasmas, Nanostructures and Solids, by V. AstapenkoNew Developments in Photon and Materials Research, Chapter 3: "Polarizational Bremsstrahlung: A Review", by S. Williams Polarizational bremsstrahlung contributions to the total bremsstrahlung spectrum have been observed in experiments involving relatively massive incident particles, resonance processes, and free atoms. However, there is still some debate as to whether or not there are significant polarizational bremsstrahlung contributions in experiments involving fast electrons incident on solid targets. It is worth noting that the term "polarizational" is not meant to imply that the emitted bremsstrahlung is polarized.
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Funds for the upgrades were eventually granted, but only at the cost of direct oversight by an Ad Hoc Panel created by the AEC. By this point the "conventional" designs, the stellarator and magnetic mirror, had long been working on real-world plasmas and were slowly increasing the pressures and temperatures. Astron, on the other hand, was still a long way from building its first useful E-layer, a prerequisite for plasma experiments. The Ad Hoc Panel returned a negative report, complaining that far too much effort had been put into operational issues like accelerator performance, with little or no effort into theoretical studies on whether or not the plasma would ever be stable even if an E-layer could be formed.
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As head of the Plasma Spectroscopy Group at Culham, he led a programme of rocket observations of ultraviolet spectra of the sun and stars. By placing telescopes on rockets and satellites it was possible to avoid the absorption of the ultraviolet light by the Earth's atmosphere and gain a great deal of information about the hot plasmas especially in the Sun's chromosphere and corona. Wilson then became involved in the European Space Research Organization's first astronomy satellite, the TD-1A mission, and led the British collaboration with Belgium in the S2/68 experiment which in 1972 conducted the first all sky survey in the ultraviolet. Wilson was best known for his role as "father" of the International Ultraviolet Explorer (IUE) satellite.
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At Aldermaston, using the same information, Ware's team calculated that with the 60 kJ available in the existing capacitor bank, they would reach the required conditions in a copper-covered quartz tube 2 inches in bore and 10 inches in diameter, or an all-copper version 2 inches in bore and 18 inches across. Work on both started in parallel, as Sceptre I and II. However, before either was completed, the ZETA team at Harwell had already achieved stable plasmas in August 1957. The Aldermaston team raced to complete their larger photographic system. Electrical arcing and shorting between the tube segments became a problem, but the team had already learned that "dry firing" the apparatus hundreds of times would reduce this effect.
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In an ionized gas plasma antenna, a gas is ionized to create a plasma. Unlike gases, plasmas have very high electrical conductivity so it is possible for radio frequency signals to travel through them so that they act as a driven element (such as a dipole antenna) to radiate radio waves, or to receive them. Alternatively the plasma can be used as a reflector or a lens to guide and focus radio waves from another source.Plasma Antennas: Survey of Techniques and the Current State of the Art D C Jenn, published 2003-09-29, accessed 2010-10-15 Solid-state antennas differ in that the plasma is created from electrons generated by activating thousands of diodes on a silicon chip.
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Since its formation its primary success has been the coordination of the United Nations University / International Centre for Theoretical Physics Plasma Fusion Facility (UNU/ICTP PFF) network which carries out research on 12 UNU/ICTP Dense Plasma Focus systems in 9 countries. The UNU/ICTP PFF was developed during a UNU Training Programme on Laser and Plasma Technology in 1985-86 at the University of Malaya, Kuala Lumpur. During initial tests, this plasma focus system already proved to be very cost effective, yet producing plasmas of such intense conditions that copious multi-radiations, including fusion neutrons were emitted . Six sets were constructed and given to the participants to be used as the core facilities to be installed in their new plasma focus laboratories back home.
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The interchange instability is a key issue in the field of fusion energy, where magnetic fields are used to confine a plasma in a volume surrounded by the field. The basic concept was first noted in a famous 1954 paper by Martin David Kruskal and Martin Schwarzschild, which demonstrated that a situation similar to the Rayleigh–Taylor instability in classic fluids existed in magnetically confined plasmas. The problem can occur anywhere where the magnetic field is concave with the plasma on the inside of the curve. Edward Teller gave a talk on the issue at a meeting later that year, pointing out that it appeared to be an issue in most of the fusion devices being studied at that time.
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Beams of protons and boron are converted into a plasma state that is held together by magnetic fields that are generated by the flow of particles in a cylindrical plasma itself, which is also known as a field-reversed configuration (FRC). Two such plasmas are then collided at high speed and form a cigar-shaped configuration that is up to 3 m long and 40 cm wide. The use of boron and protons in the fusion plasma does not generate high-energy neutrons like the tokamak. According to Rostoker, neutral particles are then injected tangentially at high speed onto the plasma cloud, which follow orbits at the edge of the plasma and serve as a kind of protection against the cooling of the plasma by escaping particles.
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"Uniform high spectral resolution demonstrated in arrays of TES x-ray microcalorimeters", Caroline Kilbourne et al., SPIE 2007 The detailed spectroscopy from these instruments will enable high-energy astronomers to learn about the temperature, composition, and velocity of plasmas in the Universe. Moreover, the study of specific X-ray spectral features probes the conditions of matter in extreme gravity field, such as around supermassive black holes. Flux variability adds a further dimension by linking the emission to the size of the emitting region and its evolution over time; the high timing resolution spectrometer (HTRS) on IXO will allow these types of studies in a broad energy range and with high sensitivity."Science with the XEUS High Time Resolution Spectrometer", D. Barret, 2008, Proc.
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Batteries are typically connected to the bus via a battery charge regulator, and the batteries are used to provide electrical power during periods when primary power is not available, for example when a low Earth orbit spacecraft is eclipsed by Earth. ; Thermal control : Spacecraft must be engineered to withstand transit through Earth's atmosphere and the space environment. They must operate in a vacuum with temperatures potentially ranging across hundreds of degrees Celsius as well as (if subject to reentry) in the presence of plasmas. Material requirements are such that either high melting temperature, low density materials such as beryllium and reinforced carbon–carbon or (possibly due to the lower thickness requirements despite its high density) tungsten or ablative carbon–carbon composites are used.
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This emission is sent to a spectrometer (located in big purple box), where it is dispersed over a finite wavelength range — which is centered on the emission line of interest — by a pair of optical gratings. However, because the collected emission is dominated by radiation from along the beam path, the measurements are effectively localized to the intersection volume between the fiber view and the beam. On MST, this intersection volume is small (~ 2 cm3) compared to the plasma volume, allowing spatially resolved measurements of Ti and vi to be obtained. Data collected from a number of plasma discharges — for which the location of the fiber bundle system is varied — are used to construct radial profiles of the impurity ion temperature and velocity, providing important information for understanding the physics of plasmas in MST.
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He is a former member (1990) and chairman (2000) of the NASA Astronomy and Astrophysics Survey Committee (the "decadal review") and former Director of the Space Sciences Laboratory (SSL) at UCB. McKee performed the first simulations of relativistic counter-streaming plasmas as part of his Ph.D. thesis at Berkeley (1970). He began his study of the interstellar medium by pointing out the existence of reverse shocks in young supernova remnants, and he then analyzed the interaction of a supernova blast wave with interstellar clouds. Since joining the Physics and Astronomy Departments in Berkeley in 1974, he has devoted much of his research to studying processes in the interstellar medium, including evaporation of clouds, the structure of shock waves in atomic and molecular gas, and the dynamics of blast waves in both homogeneous and inhomogeous media.
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Page from "Survey of Solar Cycle Prediction Models" Scissum started teaching at Councill Training School, Huntsville's only black high school. Here she very quickly realised that teaching was not for her as she worried about the students a lot. Scissum joined NASA’s Marshall Space Flight Center as an entry level mathematician in 1964 after a recommendation from a friend and was the first African-American mathematician to be employed by Marshall. She published a NASA report in 1967, “Survey of Solar Cycle Prediction Models,” which put forward techniques for improved forecasting of the sunspot cycle. In the mid-1970s she worked as a space scientist in the Space Environment Branch of Marshall’s Space Sciences Laboratory and she led activities in Marshall’s Atmospheric, Magnetospheric, and Plasmas in Space project.
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The Tokamak Fusion Test Reactor (TFTR) was an experimental tokamak built at Princeton Plasma Physics Laboratory (PPPL) circa 1980 and entering service in 1982. TFTR was designed with the explicit goal of reaching scientific breakeven, the point where the heat being released from the fusion reactions in the plasma is equal or greater than the heating being supplied to the plasma by external devices to warm it up. The TFTR never achieved this goal, but it did produce major advances in confinement time and energy density. It was the world's first magnetic fusion device to perform extensive scientific experiments with plasmas composed of 50/50 deuterium/tritium (D-T), the fuel mix required for practical fusion power production, and also the first to produce more than 10 MW of fusion power.
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However, in the practical systems of measurement for science, technology, and commerce, such as the modern metric system of units, the macroscopic and the microscopic descriptions are interrelated by the Boltzmann constant, a proportionality factor that scales temperature to the microscopic mean kinetic energy. The microscopic description in statistical mechanics is based on a model that analyzes a system into its fundamental particles of matter or into a set of classical or quantum- mechanical oscillators and considers the system as a statistical ensemble of microstates. As a collection of classical material particles, temperature is a measure of the mean energy of motion, called kinetic energy, of the particles, whether in solids, liquids, gases, or plasmas. The kinetic energy, a concept of classical mechanics, is half the mass of a particle times its speed squared.
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An up to 45 TeV atom impacting a proton in the interstellar medium should result in the p + A process described above. Ion-electron or positron-electron plasma with magnetic confinement theoretically allows direct conversion of particle energy to electricity by the separation of the positive particles from the negative particles with magnetic deflection. Direct conversion of particle energy to thrust is theoretically simpler, merely requiring magnetically directing a neutral plasma beam. Present lab production of relativistic 5 MeV positron- electron beams mimic on a small scale the relativistic jets from compact stars, and allow small scale studies how different elements interact with 5 MeV positron-electron beams, how energy is transferred to particles, the shock effect of gamma-ray bursts, and possible direct thrust and electricity generation from neutral plasmas.
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Striations or string-like structures, also known as Birkeland currents, are seen in many plasmas, like the plasma ball, the aurora, lightning, electric arcs, solar flares, and supernova remnants.. The University of Arizona They are sometimes associated with larger current densities, and the interaction with the magnetic field can form a magnetic rope structure. High power microwave breakdown at atmospheric pressure also leads to the formation of filamentary structures. (See also Plasma pinch) Filamentation also refers to the self-focusing of a high power laser pulse. At high powers, the nonlinear part of the index of refraction becomes important and causes a higher index of refraction in the center of the laser beam, where the laser is brighter than at the edges, causing a feedback that focuses the laser even more.
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Jan M. Rost is a German theoretical physicist and director at the Max Planck Institute for the Physics of Complex Systems in Dresden heading the research department Finite Systems. He was awarded the status of Fellow in the American Physical Society, after nomination by the Division of Atomic, Molecular & Optical Physics in 2007, for seminal investigations of correlated doubly excited states, threshold fragmentation in few-body Coulombic systems and small clusters, pendular states of linear molecules, and for elucidating the role of correlation and relaxation in ultracold plasmas and Rydberg gases. His research interests reach from ultracold to ultrafast dynamics in finite systems including Rydberg excitation and ionization. Former group leaders of his department are among others Andreas Buchleitner, Andreas Becker, Klaus Hornberger, Stefan Skupin, Nina Rohringer and Thomas Pohl.
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A great debate broke out in the ICF establishment as a result. One group suggested that they attempt to build a laser of this power; Leonardo Mascheroni and Claude Phipps designed a new type of hydrogen fluoride laser that was pumped by high-energy electrons that would be able to reach the 100 MJ limit. Others used the same data and new versions of their computer simulations based on these experiments that suggested that careful shaping of the laser pulse and using more beams spread more evenly showed that ignition and net energy gains could be achieved with a laser between 5 and 10 MJ.John Lindl, Development of the Indirect-Drive Approach to Inertial Confinement Fusion and the Target Physics Basis for Ignition and Gain, Physics of Plasmas Vol. 2, No. 11, November 1995; pp.
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Another hypothesis explains Hessdalen lights as a product of piezoelectricity generated under specific rock strains, because many crystal rocks in Hessdalen valley include quartz grains which produce an intense charge density. In a 2011 paper, based on the dusty plasma theory of Hessdalen lights, Gerson Paiva and Carlton Taft suggested that piezoelectricity of quartz cannot explain a peculiar property assumed by the Hessdalen lights phenomenonthe presence of geometrical structures in its center. Paiva and Taft have shown a mechanism of light ball cluster formation in Hessdalen lights by nonlinear interaction of ion-acoustic and dusty- acoustic waves with low frequency geoelectromagnetic waves in dusty plasmas. The theoretical velocity of ejected light balls is about , in good agreement with the observed velocity of some ejected light balls, estimated at .
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His Ph.D. was the first to be granted by a Chilean University for a thesis in experimental physics. The results of his thesis were published in the journal Physical Review Letters, being this the first time an article in experimental plasma physics produced in Chile was accepted in that prestigious journal. When he arrived at the Comisión Chilena de Energía Nuclear, he started to work in plasmas driven by small transient electrical discharges and small pulsed power devices: z-pinch, capillary discharges and plasma focus. His work has contributed to understand that it is possible to scale the plasma focus in a wide range of energies and sizes, keeping the same value of ion density, magnetic field, plasma sheath velocity, Alfvén speed and the quantity of energy per particle.
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Khimera is a software product from Kintech Lab intended for calculation of the kinetic parameters of microscopic processes, thermodynamic and transport properties of substances and their mixtures in gases, plasmas and also of heterogeneous processes. The development of a kinetic mechanism is a key stage of present-day technologies for the creation of hi-tech devices and processes in a wide range of fields, such as microelectronics, chemical industry, and the design and optimization of combustion engines and power stations. Khimera with Chemical WorkBench, another software product from Kintech Lab, allows both the development of complex physical and chemical mechanisms and their validation. Essential feature of Khimera is its user-friendly interface for importing and utilizing the results of quantum-chemical calculations for estimating rate constants of elementary processes and thermodynamic and transport properties.
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Anatoly Ivanovich Larkin (; October 14, 1932 – August 4, 2005) was a Russian theoretical physicist, universally recognised as a leader in theory of condensed matter, and who was also a celebrated teacher of several generations of theorists. Anatoly Larkin, world-renowned physicist, dies: News Releases: UMNnews: U of M Born in a small town of Kolomna in Moscow region, Larkin went on to receive his education at the Moscow Engineering Physics Institute. He worked on his PhD on the properties of plasmas under the supervision of A.B.Migdal and later received the degree of Doctor of Science (1965) for studies of superconductivity. Research at the I.V. Kurchatov Institute in Moscow (1957–66) was followed by nearly 40 years of work at the L.D.Landau Institute for Theoretical Physics in Chernogolovka, Moscow region, where he moved in 1966.
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An electric arc provides an energetic demonstration of electric current The process by which electric current passes through a material is termed electrical conduction, and its nature varies with that of the charged particles and the material through which they are travelling. Examples of electric currents include metallic conduction, where electrons flow through a conductor such as metal, and electrolysis, where ions (charged atoms) flow through liquids, or through plasmas such as electrical sparks. While the particles themselves can move quite slowly, sometimes with an average drift velocity only fractions of a millimetre per second, the electric field that drives them itself propagates at close to the speed of light, enabling electrical signals to pass rapidly along wires. Current causes several observable effects, which historically were the means of recognising its presence.
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At the beginning of 2006, the Z machine produced plasmas with announced temperatures in excess of 2 billion Kelvin (2 × 10 K) , 3.6 billion °F (2 billion °C) or 172 keV, even reaching a peak at 3.7 × 10 K, 6.6 billion °F (3.7 billion °C) or 319 keV. It was achieved in part by replacing the tungsten wires with thicker steel wires. This temperature, which enables a 10% to 15% efficiency in converting electrical energy to soft x-rays, was much higher than anticipated (3 to 4 times the kinetic energy of the incoming wires on axis). The Guinness Book Of Records formerly listed it as the highest human-achieved temperature (the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider have since produced higher temperatures).
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This led to the original idea for the production of p-nuclei: free protons (the nuclei of hydrogen atoms are present in stellar plasmas) should be captured on heavy nuclei (seed nuclei) also already present in the stellar plasma (previously produced in the s-process and/or r-process). Such proton captures on stable nuclides (or nearly stable), however, are not very efficient in producing p-nuclei, especially the heavier ones, because the electric charge increases with each added proton, leading to an increased repulsion of the next proton to be added, according to Coulomb's law. In the context of nuclear reactions this is called a Coulomb barrier. The higher the Coulomb barrier, the more kinetic energy a proton requires to get close to a nucleus and be captured by it.
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Stellarators are one of the first fusion power concepts, originally designed by Princeton astrophysicist Lyman Spitzer in 1952 while riding the chairlifts at Aspen. Spitzer, considering the motion of plasmas in the stars, realized that any simple arrangements of magnets would not confine a plasma inside a machine - the plasma would drift across the fields and eventually strike the vessel. His solution was very simple; by bending the machine through a 180 degree twist, forming a figure-eight instead of a donut, the plasma would alternately find itself on the inside or outside of the vessel, drifting in opposite directions. The cancellation of net drift would not be perfect, but on paper it appeared that the delay in drift rates was more than enough to allow the plasma to reach fusion conditions.
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Professor Priest has received a number of academic awards for his research, including Hale Prize of the American Astronomical Society (2002), and was elected a Fellow of the Royal Society in the same year. He is notable in the solar physics community as something of an evangelist for the importance of magnetic reconnection in driving many solar phenomena, and as an explanation of the solar coronal heating problem. As an applied mathematician, his research interests involve constructing mathematical models for the subtle and complex ways in which magnetic fields interact with plasmas in the atmosphere of the Sun and in more exotic cosmic objects. In particular, he is trying to understand how the corona of the Sun is heated to several million degrees and how magnetic energy is converted into other forms in solar flares.
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In 1992 he was appointed director of the Max Planck Institute for Aeronomy in Lindau (Katlenburg-Lindau) in Germany, a position he held until his retirement in 1998. Hagfors was chairman of EISCAT Council from 1995 to 1996, chairman of the space science committee in the Norwegian Research Council from 1992 to 1997, and member of the Norwegian Academy of Science and Letters since 1995. He was a visiting scholar at the University of Tromsø, Norway, Nagoya University in Japan, and Lancaster University in Great Britain. Hagfors's research was very broad, comprising amongst other things ionospheric modification (heating), radar astronomy within our solar system, observations of planetary surfaces from space, techniques in radio remote sensing, scattering from rough surfaces, thermal fluctuations in complex plasmas, antennas and radio wave propagation.
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Another limitation of MHD (and fluid theories in general) is that they depend on the assumption that the plasma is strongly collisional (this is the first criterion listed above), so that the time scale of collisions is shorter than the other characteristic times in the system, and the particle distributions are Maxwellian. This is usually not the case in fusion, space and astrophysical plasmas. When this is not the case, or the interest is in smaller spatial scales, it may be necessary to use a kinetic model which properly accounts for the non- Maxwellian shape of the distribution function. However, because MHD is relatively simple and captures many of the important properties of plasma dynamics it is often qualitatively accurate and is therefore often the first model tried.
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SPARC is a tokamak that has been proposed for construction by Commonwealth Fusion Systems (CFS) in collaboration with the Massachusetts Institute of Technology (MIT) Plasma Science and Fusion Center (PSFC), with funding from Eni, Breakthrough Energy Ventures, Khosla Ventures, Temasek, Equinor, Devonshire Investors, and others. SPARC plans to prove out the technology and physics required to build a power plant based on the ARC fusion power plant concept. SPARC proposes to use powerful magnets built with new yttrium barium copper oxide (YBCO) high temperature superconductor in order to produce plasmas that generate twice as much energy as is required to sustain them at high temperatures, giving a fusion gain Q > 2. SPARC is designed to meet this mission with margin and may be capable of achieving up to 140 MW of fusion power for 10 second bursts despite being a relatively compact device.
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For this initial test with about 1 mg of helium gas injected into the evacuated plasma vessel, microwave heating was applied for a short 1.3 MW pulse. The aim for the OP 1.1 was to conduct integrated testing of the most important systems as quickly as possible and to gain first experience with the physics of the machine. More than 300 discharges with helium were done in December and January with gradually increasing temperatures finally reaching six million degrees Celsius, to clean the vacuum vessel walls and test the plasma diagnostic systems. Then, on 3 February 2016, production of the first hydrogen plasma initiated the science program. The highest temperature plasmas were produced by four-megawatt microwave heater pulses lasting one second; plasma electron temperatures reached 100 MK, while ion temperatures reached 10 MK. More than 2,000 pulses were conducted before shutdown.
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He has been the head of the Science Education Department of the Princeton Plasma Physics Laboratory since 2003, where his work is focused on creating innovative opportunities for students of all backgrounds to engage in scientific inquiry and his research is centered on plasmas as an educational tool and new methods of science communication. At Princeton University, Zwicker was previously a part-time lecturer in the Writing Program and a faculty advisor for freshmen and sophomores in Rockefeller College. Zwicker has served on several national committees on education, is a Fellow of the American Physical Society, and The American Association of Physics Teachers has named him to its list of 75 leading contributors to physics education. He was the Editor of the APS Forum on Physics and Society's newsletter and a past chair of that Forum.
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Forbidden transitions in highly charged ions resulting in the emission of visible, vacuum-ultraviolet, soft x-ray and x-ray photons are routinely observed in certain laboratory devices such as electron beam ion traps and ion storage rings, where in both cases residual gas densities are sufficiently low for forbidden line emission to occur before atoms are collisionally de-excited. Using laser spectroscopy techniques, forbidden transitions are used to stabilize atomic clocks and quantum clocks that have the highest accuracies currently available. Forbidden lines of nitrogen ([N II] at 654.8 and 658.4 nm), sulfur ([S II] at 671.6 and 673.1 nm), and oxygen ([O II] at 372.7 nm, and [O III] at 495.9 and 500.7 nm) are commonly observed in astrophysical plasmas. These lines are important to the energy balance of planetary nebulae and H II regions.
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Before the first rocket missions, the corona could be observed only in white light during the eclipses, while in the last fifty years the solar corona has been photographed in the EUV and X-rays by many satellites (Pioneer 5, 6, 7, 8, 9, Helios, Skylab, SMM, NIXT, Yohkoh, SOHO, TRACE, Hinode). The emitting plasma is almost completely ionized and very light, its density is about 10−16 \- 10−14 g/cm3. Particles are so isolated that almost all the photons can leave the Sun's surface without interacting with the matter above the photosphere: in other words, the corona is transparent to the radiation and the emission of the plasma is optically- thin. The Sun's atmosphere is not the unique example of X-ray source, since hot plasmas are present wherever in the Universe: from stellar coronae to thin galactic halos.
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The International School of Photonics (ISP) was founded in 1995. Research activities include the design and fabrication of various laser systems and laser components, investigations of non-linear phenomena in different materials using photothermal, photoacoustic and related techniques, time- and space-resolved studies on laser-induced plasmas, design and characterization of fibre-optic sensors, fabrication and characterisation of polymer fibres, preparation and investigation of photonic materials and studies on photonics theory, sponsored by funding agencies including DST, AICTE and UGC. The University Grants Commission designated Cochin University of Science and Technology as a "University with Potential for Excellence in the Field of Lasers and Optoelectronics Sciences" in March 2002, and provided a grant of Rs. 5 crore that was used to establish a Centre of Excellence in Lasers and Optoelectronics Sciences (CELOS). The Centre later merged with the International School of Photonics.
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Jensen, K.L., "Field emitter arrays for plasma and microwave source applications," Physics of Plasmas, Vol. 6, No. 5, 1999, pp. 2241–2253. Magnified pictures of a field emitter array (SEM photograph of an SRI Ring Cathode developed for the ARPA/NRL/NASA Vacuum Microelectronics Initiative by Capp Spindt) A variety of materials have been developed for field emitter arrays, ranging from silicon to semiconductor fabricated molybdenum tips with integrated gates to a plate of randomly distributed carbon nanotubes with a separate gate structure suspended above. The advantages of field emission technologies over alternative electron emission methods are: # No requirement for a consumable (gas) and no resulting safety considerations for handling a pressurized vessel # A low-power capability # Having moderate power impacts due to space-charge limits in the emission of the electrons into the surrounding plasma.
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The magnetosphere of Saturn is the cavity created in the flow of the solar wind by the planet's internally generated magnetic field. Discovered in 1979 by the Pioneer 11 spacecraft, Saturn's magnetosphere is the second largest of any planet in the Solar System after Jupiter. The magnetopause, the boundary between Saturn's magnetosphere and the solar wind, is located at a distance of about 20 Saturn radii from the planet's center, while its magnetotail stretches hundreds of Saturn radii behind it. Saturn's magnetosphere is filled with plasmas originating from both the planet and its moons. The main source is the small moon Enceladus, which ejects as much as 1,000 kg/s of water vapor from the geysers on its south pole, a portion of which is ionized and forced to co-rotate with the Saturn’s magnetic field.
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The Combined Release and Radiation Effects Satellite (CRRES) was launched on July 25, 1990, into a geosynchronous transfer orbit (GTO) for a nominal three- year mission to investigate fields, plasmas, and energetic particles inside the Earth's magnetosphere. As part of the CRRES program, the SPACERAD (Space Radiation Effects) project, managed by Air Force Geophysics Laboratory, investigated the radiation environment of the inner and outer radiation belts and measured radiation effects on state-of-the-art microelectronics devices. CRRES aboard Atlas I Other magnetospheric, ionospheric, and cosmic ray experiments were also included onboard CRRES and supported by NASA or the Office of Naval Research. The chemical release project was managed by NASA/MSFC and utilized the release of chemicals from onboard canisters at low altitudes near dawn and dusk perigee times and at high altitudes near local midnight.
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In his scientific work, Lightman has made contributions to the theory of astrophysical processes under extreme temperatures and densities. In particular, his research has focused on relativistic gravitation theory, the structure and behavior of accretion disks, stellar dynamics, radiative processes, and relativistic plasmas. Some of his significant achievements are his discovery, with Douglas Eardley, of a structural instability in orbiting disks of matter, called accretion disks, that form around massive condensed objects such as black holes, with wide application in astronomy;Astrophysical Journal Letters, vol. 187, pg. L1 (1974) his proof, with David L. Lee, that all gravitation theories obeying the Weak Equivalence Principle (the experimentally verified fact that all objects fall with the same acceleration in a gravitational field) must be metric theories of gravity, that is, must describe gravity as a geometrical warping of time and space;Physical Review D, vol.
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Guenter E. Brueckner (1934–1998)Obituary was a solar physicist who spent much of his career at the US Naval Research Lab. His life's efforts included research into aspects of the sun relevant to radio signal quality, terrestrial weather, space weather and applications of plasmas such as in fusion energy. He is known for work on coronal mass ejections;CME background various innovations in solar observing optical systems,Tandem Wadsworth in particular the Skylab mission, design and development (with John-David F. Bartoe) of the Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) on the Upper Atmosphere Research Satellite (UARS); and for being the principal investigator for the LASCO instrument.Google results on Br and LASCO In the 1970s, he worked with Richard Tousey to make several notable observations including the coronal mass ejections mentioned above, lithium ions in solar flares,parroting from reference [20] in article and various other things.
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This was initially considered as a way to improve the safety factor, but during the design, it was also noticed that this would make it much easier to build the system mechanically, as it reduced the net forces across the chamber that are trying to force the torus towards the centre of the major axis. Ideally, the magnets surrounding the chamber should be more curved at the top and bottom and less on the inside and outsides in order to support these forces, which leads to something like an oval shape that the D closely approximated. The flatter shape on the inside edge was also easier to support due to the larger, flatter surface. While exploring the stability of various plasma shapes on a computer, the team noticed that non-circular plasmas did not exactly cancel out the vertical drift that the twisted fields have originally been introduced to solve.
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Average plasma displays have become one quarter the thickness from 2006 to 2011 In late 2006, analysts noted that LCDs overtook plasmas, particularly in the 40-inch (1.0 m) and above segment where plasma had previously gained market share."Shift to large LCD TVs over plasma", MSNBC, November 27, 2006, retrieved 2007-08-12. Another industry trend is the consolidation of manufacturers of plasma displays, with around 50 brands available but only five manufacturers. In the first quarter of 2008, a comparison of worldwide TV sales breaks down to 22.1 million for direct-view CRT, 21.1 million for LCD, 2.8 million for Plasma, and 0.1 million for rear- projection."LCD televisions outsell plasma 8 to 1 worldwide" , Digital Home, 21 May 2008, retrieved 2008-06-13. Until the early 2000s, plasma displays were the most popular choice for HDTV flat panel display as they had many benefits over LCDs.
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A good example of nonlinear electromagnetics is in high energy dense plasmas, where vortical phenomena occur which seemingly violate the second law of thermodynamics by increasing the energy gradient within the electromagnetic field and violate Maxwell's laws by creating ion currents which capture and concentrate their own and surrounding magnetic fields. In particular Lorentz force law, which elaborates Maxwell's equations is violated by these force free vortices. These apparent violations are due to the fact that the traditional conservation laws in classical and quantum electrodynamics (QED) only display linear U(1) symmetry (in particular, by the extended Noether theorem, conservation laws such as the laws of thermodynamics need not always apply to dissipative systems, which are expressed in gauges of higher symmetry). The second law of thermodynamics states that in a closed linear system entropy flow can only be positive (or exactly zero at the end of a cycle).
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The coronal and solar wind plasmas are highly electrically conductive, meaning the magnetic field lines and the plasma flows are effectively "frozen" together and the magnetic field cannot diffuse through the plasma on time scales of interest. In the solar corona, the magnetic pressure greatly exceeds the plasma pressure and thus the plasma is primarily structured and confined by the magnetic field. With increasing altitude through the corona, solar wind acceleration results in the flow momentum exceeding the restraining magnetic tension force and the coronal magnetic field is dragged out by the solar wind to form the HMF. The dynamic pressure of the wind dominates over the magnetic pressure through most of the Solar System (or heliosphere), so that the magnetic field is pulled into an Archimedean spiral pattern (the Parker spiralParker, E. N., "Dynamics of the Interplanetary Gas and Magnetic Fields", (1958) Astrophysical Journal, vol.
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In the late 1960s, magnetic-confinement fusion research at MIT was carried out on small-scale "table-top" experiments at the Research Laboratory for Electronics and the Francis Bitter Magnet Laboratory. At this time, the Soviet Union was developing a tokamak (though this was unknown in the United States), and Princeton Plasma Physics Laboratory (PPPL) was developing the stellarator. Bruno Coppi was working at the Institute for Advanced Study at Princeton University and was interested in the basic plasma physics problem of plasma resistivity at high values of the streaming parameter, as well as the behavior of magnetically confined plasmas at very high field strengths (≥ 10 T). In 1968, Coppi attended the third IAEA International Conference on Plasma Physics and Controlled Nuclear Fusion Research at Novosibirsk. At this conference, Soviet scientists announced that they had achieved electron temperatures of over 1000 eV in a tokamak device (T-3).
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The clotting times of both the initial dRVVT assay and confirmatory test are normalized and then used to determine a ratio of time without phospholipid excess to time with phospholipid excess. In general, a ratio of greater than 1.3 is considered a positive result and implies that the patient may have antiphospholipid antibodies. The dRVVT test has a higher specificity than the aPTT test for the detection of lupus anticoagulant, because it is not influenced by deficiencies or inhibitors of clotting factors VIII, IX or XI as the venom mainly activates only factors V and X. However dRVVT tests are strongly affected by the new direct oral anticoagulants (DOACs) and false positive LA results are obtained particularly with rivaroxaban. It is now possible to specifically remove DOACs from test plasmas with activated carbon and enable the correct diagnosis of LA with the dRVVT system despite their initial presence.
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Datta grew up in India along with elder brother Jyotirmoy Datta a noted journalist; his father B.N. Dutt a scion of two land owning families from Khulna and Jessore in south central Bengal (British India) was an eminent sugar-refining engineer and on his mother's side a relative of Michael Madhushudan Dutt the famed poet. He received a master's degree in theoretical plasma physics from Boston College in 1974 under the direction of Gabor Kalman.G. Kalman, T. Datta, KI Golden, Approximation schemes for strongly coupled plasmas, Physical Review A 12 (3), 1125 Datta also worked at the Jet Propulsion laboratory (JPL) in Pasadena, California, as a pre-doctoral NASA research associate of Robert Somoano. He also collaborated with Carl H. Brans at Loyola University New Orleans on a gravitational problem of frame dragging and worked with John Perdew on the behavior of charge density waves in jellium.
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As a simple example from the physics of magnetically confined plasmas, consider an axisymmetric system with circular, concentric magnetic flux surfaces of radius r (a crude approximation to the magnetic field geometry in an early tokamak but topologically equivalent to any toroidal magnetic confinement system with nested flux surfaces) and denote the toroidal angle by \zeta and the poloidal angle by \theta. Then the Toroidal/Poloidal coordinate system relates to standard Cartesian Coordinates by these transformation rules: : x = (R_0 +r \cos \theta) \cos\zeta : y = s_\zeta (R_0 + r \cos \theta) \sin\zeta : z = s_\theta r \sin \theta. where s_\theta = \pm 1, s_\zeta = \pm 1. The natural choice geometrically is to take s_\theta = s_\zeta = +1, giving the toroidal and poloidal directions shown by the arrows in the figure above, but this makes r,\theta,\zeta a left-handed curvilinear coordinate system.
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However, a contrast ratio generated by this method is misleading, as content would be essentially unwatchable at such settings.Google books – Digital Signage Broadcasting By Lars-Ingemar LundströmGoogle books – Instrument Engineers' Handbook: Process control and optimization By Béla G. LiptákGoogle books – Computers, Software Engineering, and Digital Devices By Richard C. Dorf Each cell on a plasma display must be precharged before it is lit, otherwise the cell would not respond quickly enough. This precharging means the cells cannot achieve a true black,, whereas an LED backlit LCD panel can actually turn off parts of the backlight, in "spots" or "patches" (this technique, however, does not prevent the large accumulated passive light of adjacent lamps, and the reflection media, from returning values from within the panel). Some manufacturers have reduced the precharge and the associated background glow, to the point where black levels on modern plasmas are starting to become close to some high-end CRTs Sony and Mitsubishi produced ten years before the comparable plasma displays.
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There are many systems throughout the physical world that can be modeled as anharmonic oscillators in addition to the nonlinear mass-spring system. For example, an atom, which consists of a positively charged nucleus surrounded by a negatively charged electronic cloud, experiences a displacement between the center of mass of the nucleus and the electronic cloud when an electric field is present. The amount of that displacement, called the electric dipole moment, is related linearly to the applied field for small fields, but as the magnitude of the field is increased, the field-dipole moment relationship becomes nonlinear, just as in the mechanical system. Further examples of anharmonic oscillators include the large-angle pendulum; nonequilibrium semiconductors that possess a large hot carrier population, which exhibit nonlinear behaviors of various types related to the effective mass of the carriers; and ionospheric plasmas, which also exhibit nonlinear behavior based on the anharmonicity of the plasma.
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ASPERA-4: An acronym for "Analyzer of Space Plasmas and Energetic Atoms," ASPERA-4 investigated the interaction between the solar wind and the Venusian atmosphere, determine the impact of plasma processes on the atmosphere, determine global distribution of plasma and neutral gas, study energetic neutral atoms, ions and electrons, and analyze other aspects of the near Venus environment. ASPERA-4 is a re-use of the ASPERA-3 design used on Mars Express, but adapted for the harsher near-Venus environment. MAG: The magnetometer is designed to measure the strength of Venus's magnetic field and the direction of it as affected by the solar wind and Venus itself. It mapped the magnetosheath, magnetotail, ionosphere, and magnetic barrier in high resolution in three-dimensions, aid ASPERA-4 in the study of the interaction of the solar wind with the atmosphere of Venus, identify the boundaries between plasma regions, and carry planetary observations as well (such as the search for and characterization of Venus lightning).
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The Nonequilibrium Gas and Plasma Dynamics Laboratory (NGPDL) at the Aerospace Engineering Department of the University of Colorado Boulder is headed by Professor Iain D. Boyd and performs research of nonequilibrium gases and plasmas involving the development of physical models for various gas systems of interest, numerical algorithms on the latest supercomputers, and the application of challenging flows for several exciting projects. The lab places a great deal of emphasis on comparison of simulation with external experimental and theoretical results, having ongoing collaborative studies with colleagues at the University of Michigan such as the Plasmadynamics and Electric Propulsion Laboratory, other universities, and government laboratories such as NASA, United States Air Force Research Laboratory, and the United States Department of Defense. Current research areas of the NGPDL include electric propulsion, hypersonic aerothermodynamics, flows involving very small length scales (MEMS devices), and materials processing (jets used in deposition thin films for advanced materials). Due to nonequilibrium effects, these flows cannot always be computed accurately with the macroscopic equations of gas dynamics and plasma physics.
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It is concerned with advancing these new laser-induced accelerator concepts, as well as with the production and investigation of intense photon and particle beams, including their interaction with matter. Therefore the main activities of the institute are emphasized on the development of high intensity lasers, new concepts for laser-driven particle acceleration, x-ray spectroscopy and strong-field quantum electrodynamics, as well as on the physics of hot dense plasmas. Apart from that the Helmholtz Institute Jena aims to contribute to the further development of the research facilities at the Helmholtz center GSI, especially the future project FAIR (Facility for Antiproton and Ion Research), and DESY with the free-electron laser (FEL) photon sources FLASH and XFEL (European XFEL).„Helmholtz-Institut Jena“ kommt - press release of BMBF, DESY, Friedrich-Schiller University Jena, GSI, Helmholtz-Gemeinschaft from June 25th, 2009 In cooperation with the FSU Jena a completely diode- pumped laser system of the high energy petawatt class (HEPW) with the POLARIS laser is realized in the building of the Helmholtz Institute Jena.
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Waves in plasmas are notoriously difficult to understand and describe analytically, but computer simulations, carried out by Thomas Bogdan and colleagues in 2003, seem to show that Alfvén waves can transmute into other wave modes at the base of the corona, providing a pathway that can carry large amounts of energy from the photosphere through the chromosphere and transition region and finally into the corona where it dissipates it as heat. Another problem with wave heating has been the complete absence, until the late 1990s, of any direct evidence of waves propagating through the solar corona. The first direct observation of waves propagating into and through the solar corona was made in 1997 with the Solar and Heliospheric Observatory space-borne solar observatory, the first platform capable of observing the Sun in the extreme ultraviolet (EUV) for long periods of time with stable photometry. Those were magneto-acoustic waves with a frequency of about 1 millihertz (mHz, corresponding to a wave period), that carry only about 10% of the energy required to heat the corona.
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The upper bound on Brayton cycle temperature for an MHD generator is not limited, so inherently an MHD generator has a higher potential capability for energy efficiency. The temperatures at which linear coal-fueled MHD generators can operate are limited by factors that include: (a) the combustion fuel, oxidizer, and oxidizer preheat temperature which limit the maximum temperature of the cycle; (b) the ability to protect the sidewalls and electrodes from melting; (c) the ability to protect the electrodes from electrochemical attack from the hot slag coating the walls combined with the high current or arcs that impinge on the electrodes as they carry off the direct current from the plasma; and (d) by the capability of the electrical insulators between each electrode. Coal-fired MHD plants with oxygen/air and high oxidant preheats would probably provide potassium seeded plasmas of about 4200°F, 10 atmospheres pressure, and begin expansion at Mach1.2. These plants would recover MHD exhaust heat for oxidant preheat, and for combined cycle steam generation.
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His research interests are extremely wide and include physics of ultra-cold gases (Bose- Einstein condensation, quantum dynamics of degenerate gases, laser induced condensation, theory of master equation and open systems for many body systems, ultra-cold Fermi gases, strongly correlated atomic and molecular systems, ultra-cold disordered and frustrated gases, ultra-cold dipolar gases, ultra-cold gases and quantum gauge theories), Quantum Information (theory of entanglement; implementations in quantum optical systems, quantum communications, quantum cryptography, quantum computers, quantum networks and entanglement percolation), Statistical Physics (stochastic processes; dynamical critical phenomena, spin glasses and disordered systems; statistical physics of neural networks; complex systems; interdisciplinary applications of statistical physics in neurophysiology, cognitive science and social psychology), Mathematical Physics (mathematical foundations of quantum mechanics and entanglement theory, rigorous statistical mechanics), Laser- matter interactions (interactions of intense laser with atoms, molecules, and plasmas; new sources of coherent XUV radiation and X-rays; ultrafast phenomena in atoms, molecules and solid state, atto-second physics, classical and complex dynamics of atomic systems), Quantum Optics (cavity quantum electrodynamics; cooling and trapping of atoms, non-classical states of light and matter; foundations of quantum mechanics; classical and quantum stochastic processes).
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According to physicist Philip Warren Anderson, the used of the term "condensed matter" to designate a field was coined by him and Volker Heine, when they changed the name of their group at the Cavendish Laboratories, Cambridge from Solid state theory to Theory of Condensed Matter in 1967, as they felt it did not exclude their interests in the study of liquids, nuclear matter, and so on. Although Anderson and Heine helped popularize the name "condensed matter", it had been present in Europe for some years, most prominently in the form of a journal published in English, French, and German by Springer-Verlag titled Physics of Condensed Matter, which was launched in 1963. The funding environment and Cold War politics of the 1960s and 1970s were also factors that lead some physicists to prefer the name "condensed matter physics", which emphasized the commonality of scientific problems encountered by physicists working on solids, liquids, plasmas, and other complex matter, over "solid state physics", which was often associated with the industrial applications of metals and semiconductors. References to "condensed" state can be traced to earlier sources.
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Given the choice of either pursuing a postdoctoral fellowship at the National Research Council in Canada or accepting a Civil Service Commission Junior Fellowship at a government-run research establishment of his choice in the UK, Paige chose the latter, ultimately choosing the Radar Research Establishment (RRE) in Malvern, where the research was focused entirely on pure science. Paige began working at that institution in 1955 with the title of Junior Research Fellow to the Deputy Chief Scientific Officer. In 1973, he was promoted to Deputy Chief Scientific Officer. In 1976, the RRE was incorporated into the Royal Signals and Radar Establishment. Eventually, Paige joined the RRE’s Transistor Physics Division, led by Alan Gibson, where he Paige “studied the behaviour of free carriers in semiconductors.”Clark, Colin; Professor E. G. S. Paige; The Independent; March 24, 2004; In the late 1950s he taught classes at Birmingham University and led seminars in the Physics Department of Oxford University. In 1966 Paige went to Copenhagen, where he spent six months as a visiting professor teaching a course on solid state plasmas. In 1968 he became leader of a research group investigating Rayleigh waves on semiconductor surfaces.
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Boedo has also made significant contributions in diagnostic development for plasmas. He is known for the development of high heat flux, fixed and reciprocating, scanning probes, such as that built for the NSTX tokamak, a rotating Langmuir probe, and also an innovative diagnostic to measure electron temperature with better than 400 kHz bandwidth. Main 8 Publications (by meaning and impact) -Experimental evidence of edge intrinsic momentum source driven by kinetic ion loss and edge radial electric fields in tokamaks. -Transport by intermittent convection in the boundary of the DIII-D tokamak, PoP 8 (11) 4826, 2001 -Transport by intermittency in the boundary of the DIII-D tokamak, PoP 10 (5) 1670, 2003 -Enhanced particle confinement and turbulence reduction due to ExB shear in the TEXTOR tokamak, Nuc. Fuc. 40 (7), 1397, 2000 -Edge-localized mode dynamics and transport in the scrape-off layer of the DIII-D tokamak, Nuc. Fus., 45 (10), S168, 2005 -Scaling of plasma turbulence suppression with velocity shear, PoP, 7 (9), 3663, 2000 -Suppression of temperature fluctuations and energy barrier generation by velocity shear, PRL, 49 (10), 104016, 2009 -On the harmonic technique to measure electron temperature with high time resolution, RSI, 0 (7), 2997, 1999 -Electric field-induced plasma convection in tokamak divertors, PoP, 15 (3), 2008 Other contributions (invited talks, services, etc.) 2014 APS DPP, New Orleans, Louisiana, invited talk 2008 EPS invited talk.
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