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Sample records for bk080001 pcs2 plasma

  1. A validation report about plasma collection by new bowl and tube system

    Institute of Scientific and Technical Information of China (English)

    Walter Nussbaumer

    2010-01-01

    @@ Introduction The plasma collector NGL XJC 2000 from Nigale (Si-chuan Nigale Biomedical Co Ltd,Chengdu,China) has been available since its CE certification in Europe and is distributed by the company StradisMed (Stradis-Med, Egelsbach, Germany). Due to its high conformity in design and functionality with the cell separator PCS-2 from Haemonefics disposables, originally produced for the Nigale separator can also be used with the PCS-2 for plasma collection. Therefore, the Plasma Service Tirol under the direction of Univ.-Doz.

  2. Plasma theory

    International Nuclear Information System (INIS)

    A series of lectures on plasma theory with the main headings: introduction; charged particles moving in em fields; the liquid model; transport phenomena in the plasma; wave propagation in plasmas; plasma instabilities. 57 figs. (qui)

  3. Plasma properties

    International Nuclear Information System (INIS)

    This paper discusses the following topics: MHD plasma activity: equilibrium, stability and transport; statistical analysis; transport studies; edge physics studies; wave propagation analysis; basic plasma physics and fluid dynamics; space plasma; and numerical methods

  4. Plasma accelerators

    International Nuclear Information System (INIS)

    Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating gradients. Starting with the plasma beat wave accelerator (PBWA) and laser wakefield accelerator (LWFA) schemes and the plasma wakefield accelerator (PWFA) steady progress has been made in theory, simulations and experiments. Computations are presented for the study of LWFA. (author)

  5. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  6. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  7. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  8. Plasma device

    International Nuclear Information System (INIS)

    A method is described of providing electron beam heating of a high-density plasma to drive a fast liner to implode a structured microsphere. An annular relativistic electron beam is used to heat an annular plasma to kilovolt temperatures through streaming instabilities in the plasma. Energy deposited in the annular plasma then converges on a fast liner to explosively or ablatively drive the liner to convergence to implode the structured microsphere. (U.K.)

  9. Plasma antennas

    CERN Document Server

    Anderson, Theodore

    2011-01-01

    The plasma antenna is an emerging technology that partially or fully utilizes ionized gas as the conducting medium instead of metal to create an antenna. The key advantages of plasma antennas are that they are highly reconfigurable and can be turned on and off. The disadvantage is that the plasma antennas require energy to be ionized. This unique resource provides you with a solid understanding of the efficient design and prototype development of plasma antennas, helping you to meet the challenge of reducing the power required to ionize the gas at various plasma densities. You also find thorou

  10. Plasma physics

    CERN Document Server

    Drummond, James E

    2013-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  11. Plasma undulator

    International Nuclear Information System (INIS)

    Two types of the undulator which is developed as a generator of the highly brilliant light for the synchrotron radiation sources and the free electron lasers, are newly proposed using the array of slender plasmas columns. One is the magnetic field type, in which the undulator force on the relativistic electron beam is generated with the electric current flowing through the plasma columns. The other is the electric field type, in which the undulator force is generated with the periodic variation of the density between the slender plasma columns. The production methods and stabilization ones of plasma columns are discussed. (author)

  12. Plasma reactor

    OpenAIRE

    Molina Mansilla, Ricardo; Erra Serrabasa, Pilar; Bertrán Serra, Enric

    2008-01-01

    [EN] A plasma reactor that can operate in a wide pressure range, from vacuum and low pressures to atmospheric pressure and higher pressures. The plasma reactor is also able to regulate other important settings and can be used for processing a wide range of different samples, such as relatively large samples or samples with rough surfaces.

  13. Plasma properties

    International Nuclear Information System (INIS)

    The Magneto-Fluid Dynamics Division continues to study a broad range of problems originating in plasma physics. Its principal focus is fusion plasma physics, and most particularly topics of particular significance for the world magnetic fusion program. During the calendar year 1990 we explored a wide range of topics including RF-induced transport as a plasma control mechanism, edge plasma modelling, further statistical analysis of L and H mode tokamak plasmas, antenna design, simulation of the edge of a tokamak plasma and the L-H transition, interpretation of the CCT experimental results at UCLA, turbulent transport, studies in chaos, the validity of moment approximations to kinetic equations and improved neoclassical modelling. In more basic studies we examined the statistical mechanisms of Coulomb systems and applied plasma ballooning mode theory to conventional fluids in order to obtain novel fluid dynamics stability results. In space plasma physics we examined the problem of reconnection, the effect of Alfven waves in space environments, and correct formulation of boundary conditions of the Earth for waves in the ionosphere

  14. PLASMA DEVICE

    Science.gov (United States)

    Baker, W.R.

    1961-08-22

    A device is described for establishing and maintaining a high-energy, rotational plasma for use as a fast discharge capacitor. A disc-shaped, current- conducting plasma is formed in an axinl magnetic field and a crossed electric field, thereby creating rotational kinetic enengy in the plasma. Such energy stored in the rotation of the plasma disc is substantial and is convertible tc electrical energy by generator action in an output line electrically coupled to the plasma volume. Means are then provided for discharging the electrical energy into an external circuit coupled to the output line to produce a very large pulse having an extremely rapid rise time in the waveform thereof. (AE C)

  15. Plasma universe

    International Nuclear Information System (INIS)

    Traditionally the views in our cosmic environment have been based on observations in the visual octave of the electromagnetic spectrum, during the last half-century supplemented by infrared and radio observations. Space research has opened the full spectrum. Of special importance are the X-ray-gamma-ray regions, in which a number of unexpected phenomena have been discovered. Radiations in these regions are likely to originate mainly from magnetised cosmic plasma. Such a medium may also emit synchrotron radiation which is observable in the radio region. If we try to base a model of the universe on the plasma phenomena mentioned we find that the plasma universe is drastically different from the traditional visual universe. Information about the plasma universe can also be obtained by extrapolation of laboratory experiments and magnetospheric in situ measurements of plasma. This approach is possible because it is likely that the basic properties of plasma are the same everywhere. In order to test the usefulness of the plasma universe model we apply it to cosmogony. Such an approach seems to be rather successful. For example, the complicated structure of the Saturnian C ring can be accounted for. It is possible to reconstruct certain phenomena 4-5 bilions years ago with an accuracy of better than 1 percent

  16. Plasma physics

    International Nuclear Information System (INIS)

    This report contains the papers delivered at the AEB - Natal University summer school on plasma physics held in Durban during January 1979. The following topics were discussed: Tokamak devices; MHD stability; trapped particles in tori; Tokamak results and experiments; operating regime of the AEB Tokamak; Tokamak equilibrium; high beta Tokamak equilibria; ideal Tokamak stability; resistive MHD instabilities; Tokamak diagnostics; Tokamak control and data acquisition; feedback control of Tokamaks; heating and refuelling; neutral beam injection; radio frequency heating; nonlinear drift wave induced plasma transport; toroidal plasma boundary layers; microinstabilities and injected beams and quasilinear theory of the ion acoustic instability

  17. Plasma Cleaning

    Science.gov (United States)

    Hintze, Paul E.

    2016-01-01

    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  18. Plasma technology

    International Nuclear Information System (INIS)

    IREQ was contracted by the Canadian Electrical Association to review plasma technology and assess the potential for application of this technology in Canada. A team of experts in the various aspects of this technology was assembled and each team member was asked to contribute to this report on the applications of plasma pertinent to his or her particular field of expertise. The following areas were examined in detail: iron, steel and strategic-metals production; surface treatment by spraying; welding and cutting; chemical processing; drying; and low-temperature treatment. A large market for the penetration of electricity has been identified. To build up confidence in the technology, support should be provided for selected R and D projects, plasma torch demonstrations at full power, and large-scale plasma process testing

  19. Plasma confinement

    CERN Document Server

    Hazeltine, R D

    2003-01-01

    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  20. Plasma Diagnostics

    International Nuclear Information System (INIS)

    The success in achieving peaceful fusion power depends on the ability to control a high temperature plasma, which is an object with unique properties, possibly the most complicated object created by humans. Over years of fusion research a new branch of science has been created, namely plasma diagnostics, which involves knowledge of almost all fields of physics, from electromagnetism to nuclear physics, and up-to-date progress in engineering and technology (materials, electronics, mathematical methods of data treatment). Historically, work on controlled fusion started with pulsed systems and accordingly the methods of plasma parameter measurement were first developed for short lived and dense plasmas. Magnetically confined hot plasmas require the creation of special experimental techniques for diagnostics. The diagnostic set is the most scientifically intensive part of a plasma device. During many years of research operation some scientific tasks have been solved while new ones arose. New tasks often require significant changes in the diagnostic system, which is thus a very flexible part of plasma machines. Diagnostic systems are designed to solve several tasks. As an example here are the diagnostic tasks for the International Thermonuclear Experimental Reactor - ITER: (1) Measurements for machine protection and basic control; (2) Measurements for advanced control; (3) Additional measurements for performance evaluation and physics. Every new plasma machine is a further step along the path to the main goal - controlled fusion - and nobody knows in advance what new phenomena will be met on the way. So in the planning of diagnostic construction we should keep in mind further system upgrading to meet possible new scientific and technical challenges. (author)

  1. Plasma Speaker

    OpenAIRE

    Kovář, J

    2015-01-01

    The article describes the design and construction of one-channel plasma speaker. Absence of mechanical membrane gives the plasma speaker no frequency limitation. The design consists of power source to supply control electronic for signal modulation, converter and output transformer. Modulation of audio signal is realized by integrated circuit TL 594 that provides the PWM modulation. Duty cycle and frequency is adjusted by potentiometers. Dual forward converter is used to voltage amplification...

  2. Plasma turbulence

    International Nuclear Information System (INIS)

    This paper presents an overview of the progress made in understanding plasma turbulence. It has relied heavily on numerical simulations to gain some intuition on the physical processes underlying nonlinear interaction and as a cross check for quantitative estimates derived from weak turbulence theory or DIA-based strong turbulence theory. The mathematical description of plasmas, especially those confined in a magnetic bottle, is far more complex than the Navier-Stokes fluid. Yet because of the dispersion of the plasma eigenmodes, the DIA perhaps has greater validity in a plasma than in a Navier-Stokes fluid. Recent developments in dynamical-systems theory have not yet been implemented in plasma turbulence at the level discussed in other studies for boundary-layer turbulence. This technique has promise for evaluating the behavior of large eddies, which may dominate plasma transport as a low-order system. In the collisionless, kinetic regime, where turbulence in x, v phase space has to be addressed, the new methods involving noneigenmode entities called clumps and holes, need further evolution to gain complete acceptability. For the future, a combination of analytical tools and numerical methods may afford the optimum route. Some examples of this are revireviewed

  3. Plasma metallization

    CERN Document Server

    Crowther, J M

    1997-01-01

    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  4. Plasma properties

    International Nuclear Information System (INIS)

    The topics of active research in the calendar year 1989 included: RF induced plasma transport, not only for its effects on the mean particle distribution function but also as a means to enhance confinement of particles and to eliminate relatively cold alpha particle ash; thorough statistical analysis of tokamak data; improved neoclassical transport analysis; deeper analysis of two-fluid Braginskii transport in a tokamak; modelling of the plasma edge and wall interaction problem; reformulation of ballooning mode stability analysis in particularly strong and general terms; MHD modelling of tokamak phenomena, such as H-mode transition, and giant sawteeth, description of highly elongated tokamaks; and analysis of edge plasma RF antenna interactions. Our basic plasma physics studies include: statistical mechanics of Coulomb gases in bounded domains; theory of MHD instabilities with flow; numerical scheme for kinetic equations with nontrivial collision operators, and heat flow in particle simulations induced by discreteness effects. In addition, there is a modest space plasma physics effort funded by non-DOE sources. The studies of heating of the solar corona are strongly affected by work from the fusion program. Equally, work on ballooning modes led to work in magnetotail instabilities and additional solar corona heating mechanisms. We except to keep some research effort in this area. We do not include in this proposal plans for any new work in this field

  5. Plasma dynamo

    CERN Document Server

    Rincon, F; Schekochihin, A A; Valentini, F

    2015-01-01

    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  6. Plasma properties

    International Nuclear Information System (INIS)

    A cursory examination of the research activities of the Magneto-Fluid Dynamics Division for the calendar year 1988 shows the effects of the gradual transformation of the group. Although our principal activity, fusion plasma physics research, is unchanged, the work shows closer ties to problems relevant to present experiments than previously. Most notable is the concentrated effort on tokamak equilibrium and transport. We are exploring the implication of turbulence induced transport, resistive MHD effects, neoclassical transport, and possible interpretations of transport based on classical phenomena. In addition, one of our members has chosen to focus on problems of enhanced statistical methods for interpretation of experiments. All of this activity preceded the Tokamak Transport Initiative and reflects our active involvement and concern with the world-wide tokamak program. Since equilibrium and transport are by no means the only theoretical plasma physics problems affecting fusion devices we continue substantial efforts in wave propagation and heating, particle simulation of plasmas, stability theory, enhancement of numerical algorithms, and general plasma physics. We are attempting to develop effective numerical schemes for the Boltzmann equation, adaptive grid methods for MHD, and particle simulation of boundary and antenna effects. Many of these topics reflect our continuing concern to maintain a modest effort in the development of theoretical models and tools for problems of real significance to fusion, but not necessarily of immediate highest priority. We select problems which we expect to become extremely important in the future. Our space plasma physics activities, funded by agencies other than DOE, transfers knowledge learned in fusion plasma physics to another area and conversely stimulates work also relevant to fusion problems

  7. Plasma physics and engineering

    CERN Document Server

    Fridman, Alexander

    2011-01-01

    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  8. ''Dusty plasmas''

    International Nuclear Information System (INIS)

    The field of ''dusty plasmas'' promises to be a very rewarding topic of research for the next decade or so, not only from the academic point of view where the emphasis is on developing the theory of the often complex collective and non-linear processes, but also from the point of view of applications in astrophysics, space physics, environmental and energy research. In this ''comment'' we should like to sketch the current development of this fast growing and potentially very important research area. We will discuss the new features of ''dusty'' plasmas in the most general terms and then briefly mention some successful applications and effects which have already been examined. (author)

  9. Burning plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Furth, H.P.; Goldston, R.J.; Zweben, S.J. (Princeton Univ., NJ (USA). Plasma Physics Lab.); Sigmar, D.J. (Massachusetts Inst. of Tech., Cambridge, MA (USA))

    1990-10-01

    The fraction of fusion-reaction energy that is released in energetic charged ions, such as the alpha particles of the D-T reaction, can be thermalized within the reacting plasma and used to maintain its temperature. This mechanism facilitates the achievement of very high energy-multiplication factors Q, but also raises a number of new issues of confinement physics. To ensure satisfactory reaction operation, three areas of energetic-ion interaction need to be addressed: single-ion transport in imperfectly symmetric magnetic fields or turbulent background plasmas; energetic-ion-driven (or stabilized) collective phenomena; and fusion-heat-driven collective phenomena. The first of these topics is already being explored in a number of tokamak experiments, and the second will begin to be addressed in the D-T-burning phase of TFTR and JET. Exploration of the third topic calls for high-Q operation, which is a goal of proposed next-generation plasma-burning projects. Planning for future experiments must take into consideration the full range of plasma-physics and engineering R D areas that need to be addressed on the way to a fusion power demonstration.

  10. Magnetoresistive waves in plasmas

    International Nuclear Information System (INIS)

    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed

  11. Plasmas Granulares

    OpenAIRE

    Conde López, Luis; Donoso Vargas, Jose Manuel; Sánchez Torres, Antonio; Tkachenko, Igor Mijail; Cal, Eduardo de la; Carralero Ortiz, Daniel; Pablos, José Luis

    2011-01-01

    Los plasmas granulares son gases total o parcialmente ionizados que, además de iones electrones y átomos neutros, contienen partículas sólidas con carga eléctrica. Dichas partículas cargadas, de tamaño mesoscópico, dan lugar a nuevos fenómenos colectivos con una dinámica característica. Este tipo de plasmas aparecen en sistemas físicos tan diversos como son los reactores de fusión por confinamiento magnético, los sistemas de procesado de semiconductores o en medios astrofísicos. Se presenta u...

  12. Plasma chromograninx

    DEFF Research Database (Denmark)

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F;

    2014-01-01

    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk....... Assessment of cardiovascular mortality during the first 3 years of observation showed that CgA measurement contained useful information with a hazard ratio (HR) of 5.4 (95% CI 1.7-16.4) (CgA confirm). In a multivariate setting, the corresponding HR was 5.9 (95% CI 1.8-19.1). WHEN ADDING N-TERMINAL PROBNP (NT...

  13. Plasma physics

    CERN Document Server

    Cairns, R A

    1985-01-01

    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  14. Plasma Free Metanephrines

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  15. Multiple mirror plasma confinement

    International Nuclear Information System (INIS)

    Multiple mirror plasma confinement concept is considered. A theory of plasma diffusion through a corrugated magnetic field is developed. It is shown, that multiple mirror devices hold considerable promise for confining fusion plasmas. 75 refs.; 8 figs.; 4 tabs

  16. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  17. Plasma-wall interaction; Interaction plasma paroi

    Energy Technology Data Exchange (ETDEWEB)

    Reichle, R

    2004-07-01

    This document gathers the 43 slides presented in the framework of the week long lecture 'hot plasmas 2004' and dedicated to plasma-wall interaction in a tokamak. This document is divided into 4 parts: 1) thermal load on the wall, power extraction and particle recovery, 2) basic edge plasma physics, 3) processes that drive the plasma-solid interaction, and 4) material conditioning (surface treatment...) for ITER.

  18. Lectures in plasma diagnostics

    International Nuclear Information System (INIS)

    This paper discusses the following topics on plasma diagnostics: Electric probes in flowing and magnetized plasmas; Electron cyclotron emission absorption; Magnetic diagnostics; Spectroscopy; and Thomson Scattering

  19. Fusion plasma physics

    CERN Document Server

    Stacey, Weston M

    2012-01-01

    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  20. Communication through plasma sheaths

    International Nuclear Information System (INIS)

    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent

  1. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Our theoretical research on dust-plasma interactions has concentrated on three main areas: (a)studies of grain charging and applications; (b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; (c) waves in strongly coupled dusty plasmas.

  2. Plasma sweeper. [Patents

    Science.gov (United States)

    Motley, R.W.; Glanz, J.

    1982-10-25

    A device is described for coupling RF power (a plasma sweeper) from RF power introducing means to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the RF power introducing means. Means are described for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

  3. Stability of collisional plasma

    International Nuclear Information System (INIS)

    As was shown experimentally, plasma obtained in rough vacuum is especially stable. Based on the simple plasma particle balance equations it was shown that the presence of sources and sinks of plasma particles leads to the undercutting of the natural oscillation spectrum in the ideal plasma. The stabilisation condition obtained indicates that the plasma stability grows as its density increases. The influence of the gas inflow into plasma is considered and it is indicated that a real plasma is stable against small perturbations. (author)

  4. Introduction to plasma dynamics

    CERN Document Server

    Morozov, A I

    2013-01-01

    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  5. Plasmas for space propulsion

    Science.gov (United States)

    Ahedo, Eduardo

    2011-12-01

    Plasma thrusters are challenging the monopoly of chemical thrusters in space propulsion. The specific energy that can be deposited into a plasma beam is orders of magnitude larger than the specific chemical energy of known fuels. Plasma thrusters constitute a vast family of devices ranging from already commercial thrusters to incipient laboratory prototypes. Figures of merit in plasma propulsion are discussed. Plasma processes and conditions differ widely from one thruster to another, with the pre-eminence of magnetized, weakly collisional plasmas. Energy is imparted to the plasma via either energetic electron injection, biased electrodes or electromagnetic irradiation. Plasma acceleration can be electrothermal, electrostatic or electromagnetic. Plasma-wall interaction affects energy deposition and erosion of thruster elements, and thus is central for thruster efficiency and lifetime. Magnetic confinement and magnetic nozzles are present in several devices. Oscillations and turbulent transport are intrinsic to the performances of some thrusters. Several thrusters are selected in order to discuss these relevant plasma phenomena.

  6. Collisionless plasmas in astrophysics

    CERN Document Server

    Belmont, Gerard; Mottez, Fabrice; Pantellini, Filippo; Pelletier, Guy

    2013-01-01

    Collisionless Plasmas in Astrophysics examines the unique properties of media without collisions in plasma physics. Experts in this field, the authors present the first book to concentrate on collisionless conditions in plasmas, whether close or not to thermal equilibrium. Filling a void in scientific literature, Collisionless Plasmas in Astrophysics explains the possibilities of modeling such plasmas, using a fluid or a kinetic framework. It also addresses common misconceptions that even professionals may possess, on phenomena such as "collisionless (Landau) damping". Abundant illustrations

  7. Industrial plasmas in academia

    International Nuclear Information System (INIS)

    The present review, written at the occasion of the 2014 EPS Innovation award, will give a short overview of the research and development of industrial plasmas within the last 30 years and will also provide a first glimpse into future developments of this important topic of plasma physics and plasma chemistry. In the present contribution, some of the industrial plasmas studied at the CRPP/EPFL at Lausanne are highlighted and their influence on modern plasma physics and also discharge physics is discussed. One of the most important problems is the treatment of large surfaces, such as that used in solar cells, but also in more daily applications, such as the packaging industry. In this contribution, the advantages and disadvantages of some of the most prominent plasmas such as capacitively- and inductively-coupled plasmas are discussed. Electromagnetic problems due to the related radio frequency and its consequences on the plasma reactor performance, and also dust formation due to chemical reactions in plasma, are highlighted. Arcing and parasitic discharges occurring in plasma reactors can lead to plasma reactor damages. Some specific problems, such as the gas supply of a large area reactor, are discussed in more detail. Other topics of interest have been dc discharges such as those used in plasma spraying where thermal plasmas are applied for advanced material processing. Modern plasma diagnostics make it possible to investigate sparks in electrical discharge machining, which surprisingly show properties of weakly-coupled plasmas. Nanosecond dielectric barrier discharge plasmas have been applied to more speculative topics such as applications in aerodynamics and will surely be important in the future for ignition and combustion. Most of the commonly-used plasma sources have been shown to be limited in their performance. Therefore new, more effective plasma sources are urgently required. With the recent development of novel resonant network antennas for new

  8. Colloidal Plasmas : Basic physics of colloidal plasmas

    Indian Academy of Sciences (India)

    C B Dwivedi

    2000-11-01

    Colloidal plasma is a distinct class of the impure plasmas with multispecies ionic composition. The distinction lies in the phase distribution of the impurity-ion species. The ability to tailor the electrostatic interactions between these colloidal particles provides a fertile ground for scientists to investigate the fundamental aspects of the Coulomb phase transition behavior. The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various acoustic modes, which are likely to exist in colloidal plasmas as well as in normal multi-ion species plasmas. Introductory ideas about the proposed physical models for the Coulomb phase transition in colloidal plasma will also be discussed.

  9. Plasmas for space propulsion

    International Nuclear Information System (INIS)

    Plasma thrusters are challenging the monopoly of chemical thrusters in space propulsion. The specific energy that can be deposited into a plasma beam is orders of magnitude larger than the specific chemical energy of known fuels. Plasma thrusters constitute a vast family of devices ranging from already commercial thrusters to incipient laboratory prototypes. Figures of merit in plasma propulsion are discussed. Plasma processes and conditions differ widely from one thruster to another, with the pre-eminence of magnetized, weakly collisional plasmas. Energy is imparted to the plasma via either energetic electron injection, biased electrodes or electromagnetic irradiation. Plasma acceleration can be electrothermal, electrostatic or electromagnetic. Plasma–wall interaction affects energy deposition and erosion of thruster elements, and thus is central for thruster efficiency and lifetime. Magnetic confinement and magnetic nozzles are present in several devices. Oscillations and turbulent transport are intrinsic to the performances of some thrusters. Several thrusters are selected in order to discuss these relevant plasma phenomena.

  10. Fundamentals of Plasma Physics

    Science.gov (United States)

    Bellan, Paul M.

    2008-07-01

    Preface; 1. Basic concepts; 2. The Vlasov, two-fluid, and MHD models of plasma dynamics; 3. Motion of a single plasma particle; 4. Elementary plasma waves; 5. Streaming instabilities and the Landau problem; 6. Cold plasma waves in a magnetized plasma; 7. Waves in inhomogeneous plasmas and wave energy relations; 8. Vlasov theory of warm electrostatic waves in a magnetized plasma; 9. MHD equilibria; 10. Stability of static MHD equilibria; 11. Magnetic helicity interpreted and Woltjer-Taylor relaxation; 12. Magnetic reconnection; 13. Fokker-Planck theory of collisions; 14. Wave-particle nonlinearities; 15. Wave-wave nonlinearities; 16. Non-neutral plasmas; 17. Dusty plasmas; Appendix A. Intuitive method for vector calculus identities; Appendix B. Vector calculus in orthogonal curvilinear coordinates; Appendix C. Frequently used physical constants and formulae; Bibliography; References; Index.

  11. Elements of plasma technology

    CERN Document Server

    Wong, Chiow San

    2016-01-01

    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  12. TFTR plasma feedback systems

    International Nuclear Information System (INIS)

    The Tokamak Fusion Test Reactor employs feedback control systems for four plasma parameters, i.e. for plasma current, for plasma major radius, for plasma vertical position, and for plasma density. The plasma current is controlled by adjusting the rate of change of current in the Ohmic Heating (OH) coil system. Plasma current is continuously sensed by a Rogowski coil and its associated electronics; the error between it and a preprogrammed reference plasma current history is operated upon by a ''proportional-plusintegral-plus-derivative'' (PID) control algorithm and combined with various feedforward terms, to generate compensating commands to the phase-controlled thyristor rectifiers which drive current through the OH coils. The plasma position is controlled by adjusting the currents in Equilibrium Field and Horizontal Field coil systems, which respectively determine the vertical and radial external magnetic fields producing J X B forces on the plasma current. The plasma major radius position and vertical position, sensed by ''B /sub theta/ '' and ''B /sub rho/ '' magnetic flux pickup coils with their associated electronics, are controlled toward preprogrammed reference histories by allowing PID and feedforward control algorithms to generate commands to the EF and HF coil power supplies. Plasma density is controlled by adjusting the amount of gas injected into the vacuum vessel. Time-varying gains are used to combine lineaveraged plasma density measurements from a microwave interferometer plasma diagnostic system with vacuum vessel pressure measurements from ion gauges, with various other measurements, and with preprogrammed reference histories, to determine commands to piezoelectric gas injection valves

  13. Plasma etching in semiconductor fabrication

    International Nuclear Information System (INIS)

    The contents of this book are: Introduction; Plasma Excitation and Reactor Design; Silicon and Silicon Dioxide Etching in Plasmas; Aluminium Etching in Chlorinated Plasmas; The Plasma Etching of III/V Compound Semiconductors; Operating Frequency and the Plasma; Probe Characteristics and Plasma Measurements of an Electrotech Planar Plasma Etcher; The RF Voltage/Current Characteristics and Related DC Negative Bias Properties of an Electrotech Flat Bed Planar Plasma Etcher; and Methods of Reducing the Etch Rate of Positive Photoresist Masks During Plasma Etching

  14. Reviews of plasma physics

    CERN Document Server

    2008-01-01

    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  15. Plasma Ion Sources

    International Nuclear Information System (INIS)

    A wide variety of ion source types has been developed. Ion sources can provide beams of hundreds of amperes for fusion applications, nano-amperes for microprobe trace analysis and broad beams for ion implantation, space thrusters, industrial polymerisation and food sterilisation. Also it can be used in medical, military and accelerators applications. In this paper, three different types of plasma ion sources with different means for producing the discharge current and the ions extracting current from the plasma are studied. The various plasma described include, d.c glow discharge plasma, arc discharge plasma and radio frequency discharge plasma

  16. Reviews of plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Shafranov, Vitalii Dmitrievich (ed.); Bakunin, Oleg G. (comps.) [Rossijskij Nauchnyj Tsentr ' ' Kurchatovskij Inst.' ' , Moscow (Russian Federation). Nuclear Fusion Inst.; Rozhansky, V. [St. Petersburg State Polytechnical Univ. (Russian Federation)

    2008-07-01

    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  17. Reviews of plasma physics

    International Nuclear Information System (INIS)

    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  18. Plasma amino acids

    Science.gov (United States)

    Plasma amino acids is a screening test done on infants that looks at the amounts of amino ... Laboratory error High or low amounts of individual plasma amino acids must be considered with other information. ...

  19. Plasma physics an introduction

    CERN Document Server

    Fitzpatrick, Richard

    2014-01-01

    Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics.

  20. Ultracold Neutral Plasmas

    OpenAIRE

    Killian, T. C.; Pattard, T.; Pohl, T.; Rost, J. M.

    2006-01-01

    Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new frontier in the study of neutral plasmas, which traditionally deals with much hotter systems, but they also blur the boundaries of plasma, atomic, condensed matter, and low temperature physics. Modelling these plasmas challenges computational techniques and ...

  1. Plasma-wall interaction

    International Nuclear Information System (INIS)

    This document gathers the 43 slides presented in the framework of the week long lecture 'hot plasmas 2004' and dedicated to plasma-wall interaction in a tokamak. This document is divided into 4 parts: 1) thermal load on the wall, power extraction and particle recovery, 2) basic edge plasma physics, 3) processes that drive the plasma-solid interaction, and 4) material conditioning (surface treatment...) for ITER

  2. Wave and plasma heating

    International Nuclear Information System (INIS)

    In the field of wave heating absorption studies of plasma magnetic waves in the theta pinch are extended to axially inhomogeneous waves. In the Plasmaus 4 experiment direct plasma production has been accomplished for overcritical densities and high magnetic fields. The numerical methods developed at IPF for plasma simulation studies have been applied successfully to further problems. (orig./GG)

  3. Plasma research in China

    International Nuclear Information System (INIS)

    This paper reports that, in China, the research work in the field of nuclear fusion and plasma physical began to study the space plasma physics. In recent years, the plasma applications have been emphasized. The experimental and theoretical studies in these fields have been carried out

  4. Basic concept in plasma diagnostics

    OpenAIRE

    Rai, V. N.

    2014-01-01

    This paper presents the basic concept of various plasma diagnostics used for the study of plasma characteristics in different plasma experiments ranging from low temperature to high energy density plasma.

  5. Physics of Partially Ionized Plasmas

    Science.gov (United States)

    Krishan, Vinod

    2016-05-01

    Figures; Preface; 1. Partially ionized plasmas here and everywhere; 2. Multifluid description of partially ionized plasmas; 3. Equilibrium of partially ionized plasmas; 4. Waves in partially ionized plasmas; 5. Advanced topics in partially ionized plasmas; 6. Research problems in partially ionized plasmas; Supplementary matter; Index.

  6. Plasma diagnostics in industry

    International Nuclear Information System (INIS)

    Plasma processing forms an invaluable part of semiconductor device manufacturing. For the most part, commercial tools have relied on an empirical process for their evolution and relied exclusively on plasma characterization only at the development stage. As this industry advances there is the need to provide non-invasive plasma characterization and diagnostics on the processing equipment, in order to provide more control over the plasma properties. We outline some of the typical configurations used in the industry and describe two of the measurement techniques we have developed for the characterization of these industrial plasma sources. (author)

  7. Modeling TFTR plasma physics

    International Nuclear Information System (INIS)

    Recent studies of plasma transport and particle trajectories expected in the Tokamak Fusion Test Reactor (TFTR) have been used to assess plasma performance, to plan for experimental operations, and to make decisions on hardware design and allocation of resources. These studies include definition of a standard plasma transport model, computing the source of fast neutrons which activate the structure, variation of assumptions concerning plasma confinement and impurity influx, definition of the optimum neutral beam pulse length and beamline orientation, investigation of the effects of different heating profiles, investigation of pellet injection, and definition of overall plasma performance and its role in extrapolating TFTR results to design more advanced tokamak reactors. (orig.)

  8. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  9. Plasma diagnostics in industry

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, M.B.; Lawler, J.F. [Scientific Systems Ltd, Howth Junction Business Park, Kilbarrack, Dublin 5 (Ireland)

    2000-12-01

    Plasma processing forms an invaluable part of semiconductor device manufacturing. For the most part, commercial tools have relied on an empirical process for their evolution and relied exclusively on plasma characterization only at the development stage. As this industry advances there is the need to provide non-invasive plasma characterization and diagnostics on the processing equipment, in order to provide more control over the plasma properties. We outline some of the typical configurations used in the industry and describe two of the measurement techniques we have developed for the characterization of these industrial plasma sources. (author)

  10. ECR Plasma Photos

    International Nuclear Information System (INIS)

    Complete text of publication follows. In order to observe and study systematically the plasma of electron cyclotron resonance (ECR) ion sources (ECRIS) we made a high number of high-resolution visible light plasma photos and movies in the ATOMKI ECRIS Laboratory. This required building the ECR ion source into an open plasma device, temporarily. An 8MP digital camera was used to record photos of plasmas made from He, methane, N, O, Ne, Ar, Kr, Xe gases and from their mixtures. The effects of the main external setting parameters (gas pressure, gas composition, magnetic field, microwave power, microwave frequency) were studied to the shape, color and structure of the plasma. The double frequency mode (9+14 GHz) was also realized and photos of this special 'star-in-star' shape plasma were recorded. A study was performed to analyze and understand the color of the ECR plasmas. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas. To our best knowledge our work is the first systematic study of ECR plasmas in the visible light region. When looking in the plasma chamber of an ECRIS we can see an axial image of the plasma (figure 1) in conformity with experimental setup. Most of the quantitative information was obtained through the summarised values of the Analogue Digital Unit (ADU) of pixels. By decreasing the strength of the magnetic trap we clearly observed that the brightness of the central part of the plasma gradually decreases, i.e. the plasma becomes more and more 'empty'. Figure 2 shows a photo series of ECR plasma at decreasing axial magnetic field. The radial size of the plasma increased because of the ascendant resonant zone. By increasing the power of the injected microwave an optimum (or at least saturation) was found in the brightness of the plasma. We found correlation between the gas dosing rates and plasma intensities. When sweeping the frequency of the microwave in a wide region

  11. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the MFE Program. It includes Fusion Plasma Theory and Experimental Plasma Research. The Fusion Plasma Theory group has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under the Experimental Plasma Research Program, we are developing the intense, pulsed neutral-beam source (IPINS) for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of utilizing certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  12. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the MFE Porgram. It includes Fusion Plasma Theory and Experimental Plasma Research. Fusion Plasma Theory has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under Experimental Plasma Research, we are developing the intense, pulsed ion-neutral source (IPINS) for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of utilizing certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  13. Laminar Plasma Dynamos

    CERN Document Server

    Wang, Z; Barnes, C W; Barnes, D C; Wang, Zhehui; Pariev, Vladimir I.; Barnes, Cris W.; Barnes, Daniel C.

    2002-01-01

    A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As opposed to intrinsically-turbulent liquid-sodium dynamos, the proposed plasma dynamos correspond to laminar flow topology. Modest plasma parameters, 1-20 eV temperatures, 10^{19}-10^{20} m^{-3} densities in 0.3-1.0 m scale-lengths driven by velocities on the order of the Alfven Critical Ionization Velocity (CIV), self-consistently satisfy the conditions needed for the magnetic field amplication. Growth rates for the plasma dynamos are obtained numerically with different geometry and magnetic Reynolds numbers. Magnetic-field-free coaxial plasma guns can be used to sustain the plasma flow and the dynamo.

  14. Arc Plasma Torch Modeling

    CERN Document Server

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  15. Applied plasma physics

    International Nuclear Information System (INIS)

    Applied Plasma Physics is a major sub-organizational unit of the Magnetic Fusion Energy (MFE) Program. It includes Fusion Plasma Theory and Experimental Plasma Research. The Fusion Plasma Theory group has the responsibility for developing theoretical-computational models in the general areas of plasma properties, equilibrium, stability, transport, and atomic physics. This group has responsibility for giving guidance to the mirror experimental program. There is a formal division of the group into theory and computational; however, in this report the efforts of the two areas are not separated since many projects have contributions from members of both. Under the Experimental Plasma Research Program we are developing a neutral-beam source, the intense, pulsed ion-neutral source (IPINS), for the generation of a reversed-field configuration on 2XIIB. We are also studying the feasibility of using certain neutron-detection techniques as plasma diagnostics in the next generation of thermonuclear experiments

  16. Exploiting the plasma potential

    International Nuclear Information System (INIS)

    The concept of plasma potential arises from the interaction of a plasma with a boundary. Due to the high mobility of electrons, a potential difference develops between the two so that a positive space-charge region, the 'sheath', shields the plasma from the boundary. Losses of ions at the boundary, however, means that shielding is ineffective unless ions enter the sheath region with a sufficiently high velocity (the 'Bohm criterion'). Since this ion flux cannot be generated by thermal motion, there is a potential variation within the plasma itself (the 'presheath'), which accelerates the ions towards the plasma edge. The potential difference between a plasma and a boundary has been exploited in a wide variety of plasma surface engineering applications. The surface of a substrate immersed in a plasma will be subject to bombardment by ions accelerated across the sheath which will not only heat the substrate but can also sputter atoms out of the surface, modify the properties of films deposited onto the surface or result in bombarding species being incorporated into the surface. While energetic ion bombardment can be supplied by directed ion beams, it is more easily applied uniformly over complex surfaces by biasing a substrate immersed in a plasma with an appropriate negative potential, either DC or rectified rf. This is a feature of ion assisted deposition processes, both PVD and CVD, ion assisted thermochemical diffusion processes, such as plasma nitriding, and, in the limit of high bias potentials (10-100 kV), Plasma Immersion Ion Implantation (PIII or PI3 - Trade Mark). This paper reviews some of the interesting and intriguing aspects of the behaviour of low pressure rf plasmas when large perturbations occur to the potential distribution described above. These observations have been made as part of our work over the last ten years on the use of low pressure plasmas and high energy ion bombardment to extend the range of applicability of plasma nitriding, in

  17. Plasmas for medicine

    Science.gov (United States)

    von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.

    2013-09-01

    Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous

  18. Synthesis and studies of dihalophosphate of (Ge,Ti,Sb,Sn)and the compounds Br-3B.OPBrCl-2 and (Me-2 Pcs)2O

    International Nuclear Information System (INIS)

    The compounds Et3 GeOp(O)X2 were prepared by the reaction of P2O3X4 with (Et3Ge)2O in 1:1 molar ratio.Further in terest was also to study the interaction of the compounds Et-3Ge OP(0)X-2 with lewis acids (Ticl-4,Sbcl-5),and to prepare the dihalophosphate of Ti and Sb.The compounds Et-3 GeOP(O)X-2.Sbcl-5(X=F,cl)have been formed,when Et-3 GeOP(O)X-2 was reacted with Sbcl-5 in the ratio 1:1.From the Ir spectra of the above memtioned compounds it was concluded that Sbcl-5 has no ability to cleave the Ge-O bond in the compounds Et-3 GeOP(O)X-2 and therefore the adduct formation occurs as a result of interaction between the terminal oxygen atom in Et-3 GeOP(O)X-2 and Sb atom containing an empty 'd' orbital.Compound Me-3Sno- Pcl-2 has been prepared by a new method,by reaction Me-3SnNEt-2 with P-2O-3 Cl-4 in ctt-2cl-2.(23 tabs., 22 figs., 70 refs.)

  19. Plasma Biomedicine in Orthopedics

    Science.gov (United States)

    Hamaguchi, Satsohi

    2012-10-01

    Various effects of plasmas irradiation on cells, tissues, and biomaterials relevant for orthopedic applications have been examined. For direct application of plasmas to living cells or tissues, dielectric barrier discharges (DBDs) with helium flows into ambient air were used. For biomaterial processing, on the other hand, either helium DBDs mentioned above or low-pressure discharges generated in a chamber were used. In this presentation, plasma effects on cell proliferation and plasma treatment for artificial bones will be discussed. First, the conditions for enhanced cell proliferation in vitro by plasma applications have been examined. The discharge conditions for cell proliferation depend sensitively on cell types. Since cell proliferation can be enhanced even when the cells are cultured in a plasma pre-treated medium, long-life reactive species generated in the medium by plasma application or large molecules (such as proteins) in the medium modified by the plasma are likely to be the cause of cell proliferation. It has been found that there is strong correlation between (organic) hydroperoxide generation and cell proliferation. Second, effects of plasma-treated artificial bones made of porous hydroxyapatite (HA) have been examined in vitro and vivo. It has been found that plasma treatment increases hydrophilicity of the surfaces of microscopic inner pores, which directly or indirectly promotes differentiation of mesenchymal stem cells introduced into the pores and therefore causes faster bone growth. The work has been performed in collaboration with Prof. H. Yoshikawa and his group members at the School of Medicine, Osaka University.

  20. Magnetospheric plasma waves

    International Nuclear Information System (INIS)

    A brief history of plasma wave observations in the Earth's magnetosphere is recounted and a classification of the identified plasma wave phenomena is presented. The existence of plasma waves is discussed in terms of the characteristic frequencies of the plasma, the energetic particle populations and the proposed generation mechanisms. Examples are given for which plasmas waves have provided information about the plasma parameters and particle characteristics once a reasonable theory has been developed. Observational evidence and arguments by analogy to the observed Earth plasma wave processes are used to identify plasma waves that may be significant in other planetary magnetospheres. The similarities between the observed characteristics of the terrestrial kilometric radiation and radio bursts from Jupiter, Saturn and possibly Uranus are stressed. Important scientific problems concerning plasma wave processes in the solar system and beyond are identified and discussed. Models for solar flares, flare star radio outbursts and pulsars include elements which are also common to the models for magnetospheric radio bursts. Finally, a listing of the research and development in terms of instruments, missions, laboratory experiments, theory and computer simulations needed to make meaningful progress on the outstanding scientific problems of plasma wave research is given. (Auth.)

  1. Advanced plasma diagnostics for plasma processing

    Science.gov (United States)

    Malyshev, Mikhail Victorovich

    1999-10-01

    A new, non-intrusive, non-perturbing diagnostic method was developed that can be broadly applied to low pressure, weakly ionized plasmas and glow discharges-trace rare gases optical emission spectroscopy (TRG-OES). The method is based on a comparison of intensities of atomic emission from trace amounts of inert gases (He, Ne, Ar, Kr, and Xe) that are added to the discharge to intensities calculated from the theoretical model. The model assumes a Maxwellian electron energy distribution function (EEDF), computes the population of emitting levels both from the ground state and the metastable states of rare gases, and from the best fit between theory and experiment determines electron temperature (Te). Subject to conditions, TRG-OES can also yield electron density or its upper or lower limit. From the comparison of the emission from levels excited predominantly by high energy electrons to that excited by low energy electrons, information about the EEDF can be obtained. The use of TRG-OES also allows a traditionally qualitative actinometry technique (determination of concentration of radical species in plasma through optical emission) to become a precise quantitative method by including Te and rare gases metastables effects. A combination of TRG-OES, advanced actinometry, and Langmuir probe measurements was applied to several different plasma reactors and regimes of operation. Te measurements and experiments to correct excitation cross section were conducted in a laboratory helical resonator. Two chamber configuration of a commercial (Lam Research) metal etcher were studied to determine the effects of plasma parameters on plasma-induced damage. Two different methods (RF inductive coupling and ultra-high frequency coupling) for generating a plasma in a prototype reactor were also studied. Pulsed plasmas, a potential candidate to eliminate the plasma-induced damage to microelectronics devices that occurs in manufacturing due to differential charging of the wafer, have

  2. Plasma polymerization by Softplasma

    DEFF Research Database (Denmark)

    Jiang, J.; Wu, Zhenning; Benter, Maike;

    2008-01-01

    In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode...... reactive splvent (as shown in Figure 1). 1] H. Biederman, in Plasma Polymer Films. (ed.) H. Biederman. Imperial College Press, Singapore, 13-24 ~OO~· '. , [2] R. d'Agostino et.a!. in Plasma Depd~itiqn, 'Treatment, and Etching ofPolymers. (ed.) R. d'Agostino, Academic Press, U.S. (1990). [3] F. F. Shi....... Recent advances in polymer thin films prepared by plasma polymerization synthesis, structural characterization, properties and applications. Surface and Coating Technology 82, 1 (1996). [4] B. Winther-Jensen. WOO0235895A2. A method and apparatus for excitation of a plasma, (2002). [5]. K. Glejbol. EP...

  3. Introduction to Complex Plasmas

    CERN Document Server

    Bonitz, Michael; Ludwig, Patrick

    2010-01-01

    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  4. Ultracold Neutral Plasmas

    CERN Document Server

    Killian, T C; Pohl, T; Rost, J M

    2006-01-01

    Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new frontier in the study of neutral plasmas, which traditionally deals with much hotter systems, but they also blur the boundaries of plasma, atomic, condensed matter, and low temperature physics. Modelling these plasmas challenges computational techniques and theories of non-equilibrium systems, so the field has attracted great interest from the theoretical and computational physics communities. By varying laser intensities and wavelengths it is possible to accurately set the initial plasma density and energy, and charged-particle-detection and optical diagnostics allow precise measurements for comparison with theoretical predictions. Recent experiments using optical probes demonstrated that ions in the plasma equilibrate in a strongly coupled fluid phase. Strongly coupled pla...

  5. Divertor plasma detachment

    Science.gov (United States)

    Krasheninnikov, S. I.; Kukushkin, A. S.; Pshenov, A. A.

    2016-05-01

    Regime with the plasma detached from the divertor targets (detached divertor regime) is a natural continuation of the high recycling conditions to higher density and stronger impurity radiation loss. Both the theoretical considerations and experimental data show clearly that the increase of the impurity radiation loss and volumetric plasma recombination causes the rollover of the plasma flux to the target when the density increases, which is the manifestation of detachment. Plasma-neutral friction (neutral viscosity effects), although important for the sustainment of high density/pressure plasma upstream and providing the conditions for efficient recombination and power loss, is not directly involved in the reduction of the plasma flux to the targets. The stability of detachment is also discussed.

  6. Thermal plasma waste treatment

    International Nuclear Information System (INIS)

    Plasma waste treatment has over the past decade become a more prominent technology because of the increasing problems with waste disposal and because of the realization of opportunities to generate valuable co-products. Plasma vitrification of hazardous slags has been a commercial technology for several years, and volume reduction of hazardous wastes using plasma processes is increasingly being used. Plasma gasification of wastes with low negative values has attracted interest as a source of energy and spawned process developments for treatment of even municipal solid wastes. Numerous technologies and approaches exist for plasma treatment of wastes. This review summarizes the approaches that have been developed, presents some of the basic physical principles, provides details of some specific processes and considers the advantages and disadvantages of thermal plasmas in waste treatment applications. (topical review)

  7. PES fabric plasma modification

    Science.gov (United States)

    Vatuňa, T.; Špatenka, P.; Píchal, J.; Koller, J.; Aubrecht, L.; Wiener, J.

    2004-03-01

    Polyester ranks the upper position in the world fiber production — nearly 54% of the total production of synthetic fibers. Troubles connected with minimizing of the textile hydrophobicity are usually being solved by the textile fibers’ surface chemical modification, but from ecological point of view modification of fabric with low temperature plasma is superior to classical chemical wet processes. Application of various plasmas for PES treatment has been already described. To compare the effectiveness of different plasma sources we performed a series of experiment both in RF and MW plasmas. For working gas nitrogen, oxygen and their mixtures were employed. Internal plasma control was provided by measurement of optical emission spectra. The hydrophilicity degree was determined by the drop test. Paper discusses optimal conditions of the PES fabric plasma treatment.

  8. Plasma cell gingivitis

    OpenAIRE

    Chandershekhar Joshi; Pradeep Shukla

    2015-01-01

    The aim of the article is to present a report on the clinical presentation of plasma cell gingivitis with the use of herbal toothpowder. Plasma cell gingivitis [PCG] is a rare benign condition of the gingiva characterized by sharply demarcated erythematous and edematous gingivitis often extending to the mucogingival junction. As the name suggests it is diffuse and massive infiltration of plasma cells into the sub-epithelial gingival tissue. It is a hypersensitivity reaction to some antigen, o...

  9. Plasmas for spacecraft propulsion

    International Nuclear Information System (INIS)

    This review presents the basics of plasma discharges applied to electric spacecraft propulsion. It briefly reports on the mature and flown technologies of gridded ion thrusters and Hall thrusters before exploring the recent yet immature technology of plasma thrusters based on expansion from low pressure high density inductively coupled and wave-excited plasma sources, e.g. the radiofrequency helicon source. Prototype development of plasma engines for future space travel is discussed using the example of the helicon double layer thruster. A summary of highlights in electric propulsion based space missions gives some insight into the challenges of future high power missions in more remote regions of space. (topical review)

  10. Physics of Plasmas

    CERN Document Server

    Woods, Leslie Colin

    2003-01-01

    A short, self-sufficient introduction to the physics of plasma for beginners as well as researchers in a number of fields. The author looks at the dynamics and stability of magnetoplasma and discusses wave and transport in this medium. He also looks at such applications as fusion research using magnetic confinement of Deuterium plasma, solar physics with its plasma loops reaching high into the corona, sunspots and solar wind, engineering applications to metallurgy, MHD direct generation of electricity, and railguns, finally touching on the relatively new and difficult subject of dusty plasmas.

  11. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura;

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma...... membrane include ABC transporters, vacuolar (V-type) H+ pumps, and P-type pumps. These pumps all utilize ATP as a fuel for energizing pumping. This review focuses on the physiological roles of plasma membrane P-type pumps, as they represent the major ATP hydrolytic activity in this membrane....

  12. Princeton Plasma Physics Laboratory

    International Nuclear Information System (INIS)

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990

  13. Tornado plasma theory

    International Nuclear Information System (INIS)

    The formation mechanism and plasma theory of tornado are proposed. Tornado is considered as a gas discharge. Electrical fields, currents, electromagnetic forces and velocities fields have been obtained

  14. Princeton Plasma Physics Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This report discusses the following topics: principal parameters achieved in experimental devices fiscal year 1990; tokamak fusion test reactor; compact ignition tokamak; Princeton beta experiment- modification; current drive experiment-upgrade; international collaboration; x-ray laser studies; spacecraft glow experiment; plasma processing: deposition and etching of thin films; theoretical studies; tokamak modeling; international thermonuclear experimental reactor; engineering department; project planning and safety office; quality assurance and reliability; technology transfer; administrative operations; PPPL patent invention disclosures for fiscal year 1990; graduate education; plasma physics; graduate education: plasma science and technology; science education program; and Princeton Plasma Physics Laboratory reports fiscal year 1990.

  15. Laminar Plasma Dynamos

    OpenAIRE

    Wang, Zhehui; Pariev, Vladimir I.; Barnes, Cris W.; Barnes, Daniel C.

    2002-01-01

    A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As opposed to intrinsically-turbulent liquid-sodium dynamos, the proposed plasma dynamos correspond to laminar flow topology. Modest plasma parameters, 1-20 eV temperatures, 10^{19}-10^{20} m^{-3} densities in 0.3-1.0 m scale-lengths driven by velocities on the orde...

  16. The plasma universe

    International Nuclear Information System (INIS)

    The term 'Plasma Universe', coined by Hannes Alfven, emphasices the fact that plasma phenomena discovered in the laboratory and in accessible regions of space. must be important also in the rest of the universe, which consists almost entirely of matter in the plasma state. Relevant aspect of this concept will be discussed. They include the response of the plasma to electric currents, the support of magnetic-field aligned electric fields, violation of the frozen-field condition, rapid release of magnetically stored energy, acceleration of charged particles, chemical separation, and filamentary and cellular structures. (authors)

  17. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G

    1984-01-01

    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  18. Plasma Physics An Introduction to Laboratory, Space, and Fusion Plasmas

    CERN Document Server

    Piel, Alexander

    2010-01-01

    Plasma Physics gives a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The new fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a brief introduction to plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple and emphasizes the underlying concepts. T...

  19. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up

  20. Waves in unmagnetized plasma

    International Nuclear Information System (INIS)

    A review of linear and weakly non-linear theory of electron waves, ion waves and electromagnetic waves in plasmas is presented. The author restricts the discussion to an infinitely extended, homogeneous and isotropic plasma, not affected by external fields and described by Vlasov's and Maxwell's equations. (Auth.)

  1. Plasma technology directory

    International Nuclear Information System (INIS)

    The Plasma Technology Directory has two main goals: (1) promote, coordinate, and share plasma technology experience and equipment within the Department of Energy; and (2) facilitate technology transfer to the commercial sector where appropriate. Personnel are averaged first by Laboratory and next by technology area. The technology areas are accelerators, cleaning and etching deposition, diagnostics, and modeling

  2. Microwave plasma mode conversion

    International Nuclear Information System (INIS)

    The behavior of hot electrons during the process of laser-produced plasma is studied. The basic equations of mode conversion from electromagnetic waves to electrostatic waves are presented. It is shown by mode conversion, that, the resonant absorption and parametric instabilities appear simultaneously, but in different plasma regions. (M.C.K.)

  3. Introduction to Plasma Spectroscopy

    CERN Document Server

    Kunze, H-J

    2009-01-01

    Based on lectures given at the Ruhr-University of Bochum for graduate students and postgraduates starting in plasma physics as well as from low- to high-density hot plasmas, this book introduces basic ideas and fundamental concepts and typical instrumentation from the X-ray to the infrared spectral regions

  4. Atoms in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1986-01-01

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.

  5. Plasma treatment of wood

    Science.gov (United States)

    Volokitin, G. G.; Skripnikova, N. K.; Sinitsyn, V. A.; Volokitin, O. G.; Shekhovtsov, V. V.; Vaschenko, S. P.; Kuz'min, V. I.

    2016-01-01

    Plasma technology was developed to create protective-decorative coatings on the wood surfaces. Experimental investigation on applying the protective coating using the low-temperature plasma energy as well as studies of the distribution of temperature fields over the section of the treated workpiece have been carried out, and the calculated results have been compared with the experimental data.

  6. Plasma etching an introduction

    CERN Document Server

    Manos, Dennis M

    1989-01-01

    Plasma etching plays an essential role in microelectronic circuit manufacturing. Suitable for researchers, process engineers, and graduate students, this book introduces the basic physics and chemistry of electrical discharges and relates them to plasma etching mechanisms. Throughout the volume the authors offer practical examples of process chemistry, equipment design, and production methods.

  7. Atoms in dense plasmas

    International Nuclear Information System (INIS)

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs

  8. Plasma-materials interactions and edge-plasma physics research

    International Nuclear Information System (INIS)

    This report discusses the: Pisces Program; Pisces Facilities; Pisces Experiments: Materials and Surface Physics; Pisces Experiments: Edge Plasma Physics; and, Theoretical Analysis: Edge Plasma Behavior

  9. A new large-scale plasma source with plasma cathode

    International Nuclear Information System (INIS)

    A new large-scale plasma source (200 mm diameter) with a plasma cathode has been investigated. The plasma has a good spatial uniformity, operates at low electron temperature, and is highly ionized under relatively low gas pressure of about 10-4 Torr. The plasma source consists of a plasma chamber and a plasma cathode generator. The plasma chamber has an anode which is 200 mm in diameter, 150 mm in length, is made of 304 stainless steel, and acts as a plasma expansion cup. A filament-cathode-like plasma ''plasma cathode'' is placed on the central axis of this source. To improve the plasma spatial uniformity in the plasma chamber, a disk-shaped, floating electrode is placed between the plasma chamber and the plasma cathode. The 200 mm diameter plasma is measure by using Langmuir probes. As a result, the discharge voltage is relatively low (30-120 V), the plasma space potential is almost equal to the discharge voltage and can be easily controlled, the electron temperature is several electron volts, the plasma density is about 1010 cm-3, and the plasma density is about 10% variance in over a 100 mm diameter. (Author)

  10. Helical plasma thruster

    Science.gov (United States)

    Beklemishev, A. D.

    2015-10-01

    A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR® rocket engine.

  11. Plasma kinetic theory

    CERN Document Server

    Swanson, Donald Gary

    2008-01-01

    Developed from the lectures of a leading expert in plasma wave research, Plasma Kinetic Theory provides the essential material for an introductory course on plasma physics as well as the basis for a more advanced course on kinetic theory. Exploring various wave phenomena in plasmas, it offers wide-ranging coverage of the field. After introducing basic kinetic equations and the Lenard–Balescu equation, the book covers the important Vlasov–Maxwell equations. The solutions of these equations in linear and quasilinear approximations comprise the majority of kinetic theory. Another main topic in kinetic theory is to assess the effects of collisions or correlations in waves. The author discusses the effects of collisions in magnetized plasma and calculates the different transport coefficients, such as pressure tensor, viscosity, and thermal diffusion, that depend on collisions. With worked examples and problem sets that enable sound comprehension, this text presents a detailed, mathematical approach to app...

  12. Plasma based accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, Allen [Max-Planck-Institut fuer Physik, Muenchen (Germany)

    2015-05-01

    The concept of laser-induced plasma wakefields as a technique to accelerate charged particles was introduced 35 years ago as a means to go beyond the accelerating gradients possible with metallic cavities supporting radio frequency electromagnetic fields. Significant developments in laser technology have made possible the pulse intensity needed to realize this concept, and rapid progress is now underway in the realization of laser-driven plasma wakefield acceleration. It has also been realized that similar accelerating gradients can be produced by particle beams propagating in plasmas, and experimental programs have also been undertaken to study this possibility. Positive results have been achieved with electron-driven plasma wakefields, and a demonstration experiment with proton-driven wakefields is under construction at CERN. The concepts behind these different schemes and their pros and cons are described, as well as the experimental results achieved. An outlook for future practical uses of plasma based accelerators will also be given.

  13. Department of Plasma Dynamics

    International Nuclear Information System (INIS)

    The gas flow in high temperatures with regard to intensive heat transfer and chemical processes was investigated. The influence of flow rate of stabilizing gas on the electron concentration in plasma torch jet was studied. The microwave measurements of plasma parameters in middle pressure range and the time resolved measurements of the electron energy distribution in unstable plasma were carried out. A simple phase-sensitive microwave reflectometer for plasma diagnostics has been used for measuring the electron density in a positive column of glow discharge plasma in noble gases. The independance between energy conversion and charge distribution in the slender EGD channel was investigated. The discontinuities in electrogasdynamics were studied. (S.B.)

  14. Solar system plasma waves

    Science.gov (United States)

    Gurnett, Donald A.

    1995-01-01

    An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

  15. Basic plasma physics

    CERN Document Server

    Ghosh, Basudev

    2014-01-01

    Basic Plasma Physics is designed to serve as an introductory compact textbook for advanced undergraduate, postgraduate and research students taking plasma physics as one of their subject of study for the first time. It covers the current syllabus of plasma physics offered by the most universities and technical institutions. The book requires no background in plasma physics but only elementary knowledge of basic physics and mathematics. Emphasis has been given on the analytical approach. Topics are developed from first principle so that the students can learn through self-study. One chapter has been devoted to describe some practical aspects of plasma physics. Each chapter contains a good number of solved and unsolved problems and a variety of review questions, mostly taken from recent examination papers. Some classroom experiments described in the book will surely help students as well as instructors.

  16. Helical plasma thruster

    Energy Technology Data Exchange (ETDEWEB)

    Beklemishev, A. D., E-mail: bekl@bk.ru [Budker Institute of Nuclear Physics SB RAS, Novosibirsk (Russian Federation)

    2015-10-15

    A new scheme of plasma thruster is proposed. It is based on axial acceleration of rotating magnetized plasmas in magnetic field with helical corrugation. The idea is that the propellant ionization zone can be placed into the local magnetic well, so that initially the ions are trapped. The E × B rotation is provided by an applied radial electric field that makes the setup similar to a magnetron discharge. Then, from the rotating plasma viewpoint, the magnetic wells of the helically corrugated field look like axially moving mirror traps. Specific shaping of the corrugation can allow continuous acceleration of trapped plasma ions along the magnetic field by diamagnetic forces. The accelerated propellant is expelled through the expanding field of magnetic nozzle. By features of the acceleration principle, the helical plasma thruster may operate at high energy densities but requires a rather high axial magnetic field, which places it in the same class as the VASIMR{sup ®} rocket engine.

  17. Weakly relativistic plasma expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fermous, Rachid, E-mail: rfermous@usthb.dz; Djebli, Mourad, E-mail: mdjebli@usthb.dz [Theoretical Physics Laboratory, Faculty of Physics, USTHB, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria)

    2015-04-15

    Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.

  18. Transport in driven plasmas

    International Nuclear Information System (INIS)

    A plasma in contact with an external source of power, especially a source that interacts specifically with high-velocity electrons, exhibits transport properties, such as conductivity, different from those of an isolated plasma near thermal equilibrium. This is true even when the bulk of the particles in the driven plasma is near thermal equilibrium. To describe the driven plasma, we derive an adjoint equation to the inhomogeneous, linearized, dynamic Boltzmann equation. The Green's functions for a variety of plasma responses can then be generated. It is possible to modify the Chapman--Enskog [Mathematical Theory of Nonuniform Gases, 3rd ed., (Cambridge U.P., Cambridge, MA, 1970)] expansion in order to incorporate the response functions derived here

  19. Wakes in inhomogeneous plasmas

    CERN Document Server

    Kompaneets, Roman; Nosenko, Vladimir; Morfill, Gregor E

    2014-01-01

    The Debye shielding of a charge immersed in a flowing plasma is an old classic problem in plasma physics. It has been given renewed attention in the last two decades in view of experiments with complex plasmas, where charged dust particles are often levitated in a region with strong ion flow. Efforts to describe the shielding of the dust particles in such conditions have been focused on the homogeneous plasma approximation, which ignores the substantial inhomogeneity of the levitation region. We address the role of the plasma inhomogeneity by rigorously calculating the point charge potential in the collisionless Bohm sheath. We demonstrate that the inhomogeneity can dramatically modify the wake, making it non-oscillatory and weaker.

  20. Microphysics of cosmic plasmas

    CERN Document Server

    Bykov, Andrei; Cargill, Peter; Dendy, Richard; Wit, Thierry; Raymond, John

    2014-01-01

    This title presents a review of the detailed aspects of the physical processes that underlie the observed properties, structures and dynamics of cosmic plasmas. An assessment of the status of understanding of microscale processes in all astrophysical collisionless plasmas is provided. The topics discussed include  turbulence in astrophysical and solar system plasmas as a phenomenological description of their dynamic properties on all scales; observational, theoretical and modelling aspects of collisionless magnetic reconnection; the formation and dynamics of shock waves; and a review and assessment of microprocesses, such as the hierarchy of plasma instabilities, non-local and non-diffusive transport processes and ionisation and radiation processes.  In addition, some of the lessons that have been learned from the extensive existing knowledge of laboratory plasmas as applied to astrophysical problems are also covered.   This volume is aimed at graduate students and researchers active in the areas of cosmi...

  1. Innovations in plasma sensors

    Science.gov (United States)

    Zurbuchen, Thomas H.; Gershman, Daniel J.

    2016-04-01

    During the history of space exploration, ever improving instruments have continued to enable new measurements and discoveries. Focusing on plasma sensors, we examine the processes by which such new instrument innovations have occurred over the past decades. Due to risk intolerance prevalent in many NASA space missions, innovations in plasma instrumentation occur primarily when heritage systems fail to meet science requirements, functional requirements as part of its space platform, or design constraints. We will review such innovation triggers in the context of the design literature and with the help of two case studies, the Fast Imaging Plasma Spectrometer on MErcury Surface, Space ENvironment, GEochemistry, and Ranging and the Fast Plasma Investigation on Magnetosphere Multiscale. We will then discuss the anticipated needs for new plasma instrument innovations to enable the science program of the next decade.

  2. Nonthermal plasma chemistry and physics

    CERN Document Server

    Meichsner, Jurgen; Schneider, Ralf; Wagner, Hans-Erich

    2013-01-01

    In addition to introducing the basics of plasma physics, Nonthermal Plasma Chemistry and Physics is a comprehensive presentation of recent developments in the rapidly growing field of nonthermal plasma chemistry. The book offers a detailed discussion of the fundamentals of plasma chemical reactions and modeling, nonthermal plasma sources, relevant diagnostic techniques, and selected applications.Elucidating interconnections and trends, the book focuses on basic principles and illustrations across a broad field of applications. Expert contributors address environmental aspects of plasma chemist

  3. Waves in Space Plasmas Program

    International Nuclear Information System (INIS)

    The Waves in Space Plasmas (WISP) program is a joint international effort involving instrumentation to be designed and fabricated by funding from NASA and the National Research Council of Canada. The instrumentation, with a tentatively planned payload for 1986, can be used to perturb the plasma with radio waves to solve problems in ionospheric, atmospheric, magnetospheric, and plasma physics. Among the ionospheric and plasma phenomena to be investigated using WISP instrumentation are VLF wave-particle interactions, ELF/VLF propagation, traveling ionospheric disturbances and gravity wave coupling, equatorial plasma bubble phenomena, plasma wave physics such as mode-coupling, dispersion, and instabilities, and plasma physics of the antenna-plasma interactions

  4. High energy plasma accelerators

    International Nuclear Information System (INIS)

    Colinear intense laser beams ω0, kappa0 and ω1, kappa1 shone on a plasma with frequency separation equal to the electron plasma frequency ω/sub pe/ are capable of creating a coherent large longitudinal electric field E/sub L/ = mc ω/sub pe//e of the order of 1GeV/cm for a plasma density of 1018 cm-3 through the laser beat excitation of plasma oscillations. Accompanying favorable and deleterious physical effects using this process for a high energy beat-wave accelerator are discussed: the longitudinal dephasing, pump depletion, the transverse laser diffraction, plasma turbulence effects, self-steepening, self-focusing, etc. The basic equation, the driven nonlinear Schroedinger equation, is derived to describe this system. Advanced accelerator concepts to overcome some of these problems are proposed, including the plasma fiber accelerator of various variations. An advanced laser architecture suitable for the beat-wave accelerator is suggested. Accelerator physics issues such as the luminosity are discussed. Applications of the present process to the current drive in a plasma and to the excitation of collective oscillations within nuclei are also discussed

  5. Plasma Science Committee (PLSC)

    International Nuclear Information System (INIS)

    The Plasma Science Committee (PLSC) is a standing committee under the auspices of the Board on Physics and Astronomy, Commission on Physical Sciences, Mathematics, and Applications of the National Academy of Sciences--National Research Council. Plasma sciences represent a broad and diverse field. The PLSC has accepted the responsibility of monitoring the continuing development and assessing the general health of the field as whole. Although select advisory bodies have been created to address specific issues that affect plasma science, such as the Fusion Policy Advisory Committee (FPAC), the PLSC provides a focus for the plasma science community that is unique and essential. The membership of the PLSC is drawn from research laboratories in universities, industry, and government. Areas of expertise on the committee include accelerators and beams, space physics, astrophysics, computational physics and applied mathematics, fusion plasmas, fundamental experiments and theory, radiation sources, low temperature plasmas, and plasma-surface interactions. The PLSC is well prepared to respond to requests for studies on specific issues. This report discusses ion of the PLSC work

  6. Origins of magnetospheric plasma

    Science.gov (United States)

    Moore, Thomas E.

    1991-01-01

    A review is given of recent (1987-1990) progress in understanding of the origins of plasmas in the earth's magnetosphere. In counterpoint to the early supposition that geomagnetic phenomena are produced by energetic plasmas of solar origin, 1987 saw the publication of a provocative argument that accelerated ionospheric plasma could supply all magnetospheric auroral and ring current particles. Significant new developments of existing data sets, as well as the establishment of entirely new data sets, have improved the ability to identify plasma source regions and to track plasma through the magnetospheric system of boundary layers and reservoirs. These developments suggest that the boundary between ionospheric and solar plasmas, once taken to lie at the plasmapause, actually lies much nearer to the magnetopause. Defining this boundary as the surface where solar wind and ionosphere contribute equally to the plasma, it is referred to herein as the 'geopause'. It is now well established that the infusion of ionospheric O(+) plays a major role in the storm-time distention of the magnetotail and inflation of the inner magnetosphere. After more than two decades of observation and debate, the question remains whether magnetosheric are protons of solar or terrestrial origin.

  7. Origins of magnetospheric plasma

    International Nuclear Information System (INIS)

    A review is given of recent (1987-1990) progress in understanding of the origins of plasmas in the earth's magnetosphere. In counterpoint to the early supposition that geomagnetic phenomena are produced by energetic plasmas of solar origin, 1987 saw the publication of a provocative argument that accelerated ionospheric plasma could supply all magnetospheric auroral and ring current particles. Significant new developments of existing data sets, as well as the establishment of entirely new data sets, have improved the ability to identify plasma source regions and to track plasma through the magnetospheric system of boundary layers and reservoirs. These developments suggest that the boundary between ionospheric and solar plasmas, once taken to lie at the plasmapause, actually lies much nearer to the magnetopause. Defining this boundary as the surface where solar wind and ionosphere contribute equally to the plasma, it is referred to herein as the 'geopause'. It is now well established that the infusion of ionospheric O(+) plays a major role in the storm-time distention of the magnetotail and inflation of the inner magnetosphere. After more than two decades of observation and debate, the question remains whether magnetosheric are protons of solar or terrestrial origin. 161 refs

  8. Plasma Diagnostics and Plasma-Surface Interactions in Inductively Coupled Plasmas

    OpenAIRE

    Titus, Monica Joy

    2010-01-01

    The semiconductor industry's continued trend of manufacturing device features on the nanometer scale requires increased plasma processing control and improved understanding of plasma characteristics and plasma-surface interactions. This dissertation presents a series of experimental results for focus studies conducted in an inductively coupled plasma (ICP) system. First novel "on-wafer" diagnostic tools are characterized and related to plasma characteristics. Second, plasma-polymer interactio...

  9. Space electric propulsion plasmas

    International Nuclear Information System (INIS)

    This paper reports on electric thrusters which offer the promise of a substantial improvement in performance over that of conventional chemical rockets currently used in space propulsion applications. Thrust is produced in three separate classes of thrusters by: expanding an electrically heated plasma in a nozzle, accelerating a plasma through the application of an electromagnetic body force, or accelerating ions in an electric field. Each of these means of producing thrust involves plasmas that are at once different, phenomenologically rich, and worthy of separate consideration

  10. Reactor de plasma

    OpenAIRE

    Erra Serrabasa, Pilar; Molina Mansilla, Ricardo; Beltrán Serra, Eric

    2008-01-01

    Reactor de plasma. Se trata de un reactor de plasma que puede trabajar en un amplio rango de presión, desde el vacío y presiones reducidas hasta la presión atmosférica y presiones superiores. Adicionalmente el reactor de plasma tiene la capacidad de regular otros parámetros importantes y permite su uso para el tratamiento de muestras de tipología muy diversa, como por ejemplo las de tamaño relativamente grande o de superficie rugosa.

  11. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M;

    2013-01-01

    -pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds for......Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic...

  12. Unexpected high plasma cobalamin

    DEFF Research Database (Denmark)

    Arendt, Johan F B; Nexo, Ebba

    2013-01-01

    It is well-established that more than 8% of patients examined for vitamin B12 deficiency unexpectedly have increased plasma levels of the vitamin, but so far there are no guidelines for the clinical interpretation of such findings. In this review, we summarise known associations between high plasma...... cobalamin binding proteins, transcobalamin and haptocorrin. Based on current knowledge, we suggest a strategy for the clinical interpretation of unexpected high plasma cobalamin. Since a number of the associated diseases are critical and life-threatening, the strategy promotes the concept of 'think the...

  13. Plasma for cancer treatment

    Science.gov (United States)

    Keidar, Michael

    2015-06-01

    Plasma medicine is a relatively new field that grew from research in application of low-temperature (or cold) atmospheric plasmas in bioengineering. One of the most promising applications of cold atmospheric plasma (CAP) is cancer therapy. Convincing evidence of CAP selectivity towards the cancer cells has been accumulated. This review summarizes the state of the art of this emerging field, presenting various aspects of CAP application in cancer such as the role of reactive species (reactive oxygen and nitrogen), cell cycle modification, in vivo application, CAP interaction with cancer cells in conjunction with nanoparticles, and computational oncology applied to CAP.

  14. Ultracold neutral plasmas.

    Science.gov (United States)

    Killian, Thomas C

    2007-05-01

    Ultracold neutral plasmas occupy an exotic regime of plasma physics in which electrons form a swarming, neutralizing background for ions that sluggishly move in a correlated manner. Strong interactions between the charged particles give rise to surprising dynamics such as oscillations of the average kinetic energy during equilibration and extremely fast recombination. Such phenomena offer stimulating and challenging problems for computational scientists, and the physics can be applied to other environments, such as the interior of gas giant planets and plasmas created by short-pulse laser irradiation of solid, liquid, and cluster targets. PMID:17478712

  15. Plasma synthesis of nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Vollath, Dieter, E-mail: dieter.vollath@nanoconsulting.d [NanoConsulting (Germany)

    2008-12-15

    There is a huge variety of plasma processes for synthesis of nanoparticulate powders. They may be grouped with respect to operating temperature, which is the essential parameter with respect to the properties of the products. In view of industrial production, the highest degree of maturity is found in high temperature processes working under ambient pressure. For products, where well-defined properties are demanded, low temperature microwave plasma processes are best suited. Additionally, these processes allow coating of the produced particles, even with organic phases. Other processes where plasmas are involved, such as laser or flame processes coupled with electric fields have, to some extent, a high potential for development.

  16. Computing in plasma physics

    International Nuclear Information System (INIS)

    These proceedings contain the articles presented at the named conference. These concern numerical methods for astrophysical plasmas, the numerical simulation of reversed-field pinch dynamics, methods for numerical simulation of ideal MHD stability of axisymmetric plasmas, calculations of the resistive internal m=1 mode in tokamaks, parallel computing and multitasking, particle simulation methods in plasma physics, 2-D Lagrangian studies of symmetry and stability of laser fusion targets, computing of rf heating and current drive in tokamaks, three-dimensional free boundary calculations using a spectral Green's function method, as well as the calculation of three-dimensional MHD equilibria with islands and stochastic regions. See hints under the relevant topics. (HSI)

  17. Ambipolar diffusion in plasma

    International Nuclear Information System (INIS)

    Is this thesis, a numerical method for the solution of the linear diffusion equation for a plasma containing two types of ions, with the possibility of charge exchange, has been developed. It has been shown that the decay time of the electron and ion densities is much smaller than that in a plasma containing only a single type of ion. A non-linear diffusion equation, which includes the effects of an external electric field varying linearly in time, to describe a slightly ionized plasma has also been developed. It has been verified that the decay of the electron density in the presence of such an electric field is very slow. (author)

  18. Optical plasma microelectronic devices

    CERN Document Server

    Forati, Ebrahim; Dill, Thyler; Sievenpiper, Dan

    2015-01-01

    The semiconductor channel in conventional microelectronic devices was successfully replaced with an optically triggered gas plasma channel. The combination of DC and laser-induced gas ionizations controls the conductivity of the channel, enabling us to realize different electronic devices such as transistors, switches, modulators, etc. A special micro-scale metasurface was used to enhance the laser-gas interaction, as well as combining it with DC ionization properly. Optical plasma devices benefit form the advantages of plasma/vacuum electronic devices while preserving most of the integrablity of semiconductor based devices.

  19. Neutral Gas Plasma Interactions in Space Plasma

    Science.gov (United States)

    Liou, Kan

    A sounding rocket experiment, CRIT-II, involving the injection of shaped-charge barium in ionospheric plasma was conducted on May 7, 1989, to investigate Alfven's critical ionization velocity (CIV) hypothesis in space. The CRIT -II main payload was instrumented to make in situ measurements within the neutral barium beam. Among the detectors, UNH provided three energetic particle detectors and two photometers. The data from these detectors are presented. The typical features of the CIV effect were observed including plasma density enhancement, energy and momentum loss of a fast ion beam, excitation of plasma waves, and electron heating. It was found by optical observations that about 4% of the neutral barium was ionized. We believe that about one half of these barium ions were created by electron impact ionization --a CIV mechanism. The cross section for collisions between the barium atoms and the ionospheric oxygen ions was also calculated, assuming that the other half of ionizing barium ions were mainly generated by charge exchange, and found to be in the range from 1 times 10 ^{-17} cm^{-2} at a velocity of 4 km/s to 1 times 10^{-15} cm^{-2} at a velocity of 20 km/s. We also confirmed that the early observed ions were originally from the collisionally accelerated neutral oxygen which charge exchanges with the local oxygen ions. The early stage of electron heating was confirmed to be the result of lower hybrid instabilities excited by the precursor ion beam, using our quasi-linear model calculation. However, the wave spectrum during the passage of main streaming barium was found to be inconsistent with the lower hybrid instabilities proposed by current CIV theories. This could be the main reason for a relatively low ionization yield that one otherwise would expect from CRIT-II. A multi-fluid model of the wave dispersion relation for an unmagnetized beam with finite width in a magnetized plasma was also derived. We found that the nonuniform beam density effect

  20. Plasma concentrations of misonidazole

    International Nuclear Information System (INIS)

    The plasma concentrations of misonidazole doses between 0.6 and 2.0 g/m2 were analyzed in respect to the variation within the same patient and between different patients. Peak plasma levels were observed after 2 hours. The mean plasma levels of misonidazole only at 3 hours were 23.8, 47.0 and 76.5 μg/ml after misonidazole doses of 0.6, 1.2 g/m2, respectively. The half-life of misonidazole only was found to be 8.2 hours for women and 10.5 for men. Good linearity between plasma levels and drug doses was observed after administration of different single doses to the same patient within the dose range 0.6 to 2.0 g/m2. (orig.)

  1. Vol. 6: Plasma Physics

    International Nuclear Information System (INIS)

    Problems of modern physics and the situation with physical research in Ukraine are considered. Programme of the conference includes scientific and general problems. Its proceeding are published in 6 volumes. The papers presented in this volume refer to plasma physics

  2. Plasma resistant structural member

    International Nuclear Information System (INIS)

    The present invention provides a plasma resistant ceramic material of a plasma confining device for a tokamak thermonuclear device. Namely, the structural member of the present invention comprises a ceramic-based fibrous composite material having a matrix mainly comprising SiC and fibers composited in the matrix, as a constitution undergoing heat fluxes from plasmas. It is constituted such that it undergoes heat fluxes from plasmas by way of a surface in the direction having the highest heat conductivity. Since the fibers are a reinforcing material for enhancing the toughness of the SiC matrix, SiC type fibers are used. With such a constitution, the structural member has excellent properties such as high temperature strength, high temperature creeping characteristics, high heat stability, elasticity, heat conductivity and sputtering resistance, in addition to provide a high melting point (high sublimation temperature) and a low atomic weight. (N.H.)

  3. Magnetospheric Plasma Physics

    Science.gov (United States)

    Mauk, Barry H.

    Magnetospheric Plasma Physics is volume 4 of an ongoing series of review books entitled Developments in Earth and Planetary Sciences organized by the Center for Academic Publications Japan. The series is intended to stress Japanese work; however, the present volume was written by seven internationally selected authors who have reviewed works from a broad range of sources. This volume is composed of articles drawn from five lecture series presented at the Autumn College o f Plasma Physics, International Center for Theoretical Physics, Trieste, Italy, October-November 1979. The audiences for these lecture series were plasma and/or space plasma physicists, or students of the same, and the level and tone of this volume clearly reflect that condition.

  4. Physics of Plasmas

    Science.gov (United States)

    Woods, Leslie Colin

    2004-01-01

    A short, self-sufficient introduction to the physics of plasma for beginners as well as researchers in a number of fields. The author looks at the dynamics and stability of magnetoplasma and discusses wave and transport in this medium. He also looks at such applications as fusion research using magnetic confinement of Deuterium plasma, solar physics with its plasma loops reaching high into the corona, sunspots and solar wind, engineering applications to metallurgy, MHD direct generation of electricity, and railguns, finally touching on the relatively new and difficult subject of dusty plasmas. The book includes mathematical notes and 99 exercises that supplement the theory presented and thus offers the beginner an easy introduction to this exciting field. It is an equally good textbook for final year undergraduates and first year research students.

  5. Plasma formation in TBR

    International Nuclear Information System (INIS)

    In this work are presented and discussed results of the formation and equilibrium of the plasma current in TBR, a small tokamak, designed and contructed at the Instituto de Fisica of Universidade de Sao Paulo. The measured breakdown curves for H2, A and He are compared with the predictions of a simple model with reasonable agreement. The influence of stray magnetic fields in the plasma formation is investigated and conditions are chosen to facilitate the breakdown. The time profile of loop voltage and plasma current for shots with plasma equilibrium are shown. A comparison is made between experimental results and analytical-numerical model for tokamaks discharges with ohmic heating. Reasonable agreement is obtained when Z, effective atomic number, is assumed as a parameter. (Author)

  6. Plasma-Sheath Model

    Science.gov (United States)

    Riemann, Karl-Ulrich

    2012-10-01

    In typical gas discharges a quasineutral plasma is shielded from a negativ absorbing wall by a thin positive sheath that is nearly planar and collision-free. The subdivision of ``plasma'' and ``sheath'' was introduced by Langmuir and is based on a small ratio of the electron Debye lenghth λD to the dominant competing characteristic plasma length l. Depending on the special conditions, l may represent, e.g., the plasma extension, the ionization length, the ion mean free path, the ion gyro radius, or a geometric length. Strictly speaking, this subdivion is possible only in the asymptotic limit λD/l->0. The asymptotic analysis results in singularities at the ``sheath edge'' closely related to the ``Bohm criterion.'' Due to these singularities a direct smooth matching of the separate plasma and sheath soltions is not possible. To obtain a consistent smooth transition, the singular sheath edge must be bridged by an additinal narrow ``intermediate'' model zone accounting both for plasma processes (e.g., collisions) and for the first build up of space charge. Due to this complexity and to different interpretations of the ``classical'' papers by Langmuir and Bohm, the asymptotic plasma-sheath concept and the definition of the sheath edge were questioned and resulted in controversies during the last two decades. We discuss attempts to re-define the sheath edge, to account for finite values of λD/l in the Bohm criterion, and demonstrate the consistent matching of plasma and sheath. The investigations of the plasma-sheath transition discussed so far are based on a simplified fluid analysis that cannot account for the essential inhomogeneity of the boundary layer and for the dominant role of slow ions in space charge formation. Therefore we give special emphasis to the kinetic theory of the plasma-sheath transition. Unfortunately this approach results in an additional mathematical difficulty caused by ions with zero velocity. We discuss attempts to avoid this singularity by

  7. Plasma diagnostics in plasma processing for nanotechnology and nanolevel chemistry

    OpenAIRE

    Hiroshi Akatsuka

    2004-01-01

    The author reviews the role of various plasma diagnostics in plasma processing for nanotechnology, and points out some essential methods of spectroscopic methods to diagnose plasmas for nanoprocessing. Two experimental examples are discussed between the characteristics of nanomaterials and plasma parameters. One is measurement of rotation temperature in processing of carbon nanotube. The other is that of vibrational temperature in surface nitriding of titanium by nitrogen plasma processing. W...

  8. Plasma cell leukemia

    OpenAIRE

    Gertz, Moria A.; Buadi, Francis K.

    2010-01-01

    Plasma cell leukemia (PCL) is a rare, yet aggressive plasma cell (PC) neoplasm, variant of multiple myeloma (MM), characterized by high levels of PCs circulating in the peripheral blood. PCL can either originate de novo (primary PCL) or as a secondary leukemic transformation of MM (secondary PCL). Presenting signs and symptoms are similar to those seen in MM such as renal insufficiency, hypercalcemia, lytic bone lesions, anemia, and thrombocytopenia, but can also include hepatomegaly and sple...

  9. Plasma adiabatic lapse rate

    OpenAIRE

    Amendt, Peter; Bellei, Claudio; Wilks, Scott

    2012-01-01

    The plasma analog of an adiabatic lapse rate (or temperature variation with height) in atmospheric physics is obtained. A new source of plasma temperature gradient in a binary ion species mixture is found that is proportional to the concentration gradient and difference in average ionization states . Application to inertial-confinement-fusion implosions indicates a potentially strong effect in plastic (CH) ablators that is not modeled with mainline (single-fluid) simulations. An associated pl...

  10. Fe (Plasma Iron Turnover)

    OpenAIRE

    Montanaro, Zac Kime

    2011-01-01

    Fe (Plasma Iron Turnover) is a work, or compilation of interrelating works, endeavoring to generate a custom strategy for conducting experimental information exploration. Beginning with a single event in world news, the explosion of a gas plant in Western Australia in June of 2008, Fe (Plasma Iron Turnover) teases out the physical, contextual, and subtextual cues of the story to develop and articulate a methodology for discovering related events, both backwards and forwards in history, and fo...

  11. Laser studies of plasmas

    OpenAIRE

    Jacobs, Robert Michael James.; Hancock, G; Gus Hancock

    2000-01-01

    Measurement of the intrinsic properties of processing plasmas is critically important in understanding discharges so that the optimum conditions can be achieved. Several different diagnostic methods have been developed and tested.A planar probe has been used to measure the ion flux and electron temperature in both inductively coupled and capacitively coupled plasma systems, at various pressures and applied powers, using the assumption that the electron energy distribution is a Ma...

  12. Reactive plasma spraying

    OpenAIRE

    Al-Sabouni, Omar

    1999-01-01

    Reactive Plasma Spraying (RPS) with a hydrocarbon gas has been studied as a method to improve the mechanical properties of a commercially available 80: 20 nickel-chromium alloy, and subsequently as a method to reduce the oxygen content of sprayed MCrAlY coatings. A conventional d. c. plasma torch has been modified by attaching a conical graphite tube (reactor) onto the end of the gun. The powder is then sprayed through the reactor with injected reactive hydrocarbon gas. The ...

  13. Plasma jet takes off.

    OpenAIRE

    Frazer, L

    1999-01-01

    Thanks to a series of joint research projects by Los Alamos National Laboratory, Beta Squared of Allen, Texas, and the University of California at Los Angeles, there is now a more environmentally sound method for cleaning semiconductor chips that may also be effective in cleaning up chemical, bacterial, and nuclear contaminants. The Atmospheric Pressure Plasma Jet uses a type of ionized gas called plasma to clean up contaminants by binding to them and lifting them away. In contrast to the cor...

  14. Lecture notes on plasma physics

    International Nuclear Information System (INIS)

    The lectures cover the following topics in plasma physics: electrostatic plasma oscillations as described by the linearized Vlasov equation; properties of dielectric functions; the fluctuation dissipation theorem; 'dressed-particle' approach to plasma fluctuations; electron waves in a strongly magnetized plasma; propagation of ion acoustic density perturbations as described by the linearized ion Vlasov equation assuming Boltzmann distributed electrons; nonlinear waves. (Auth.)

  15. Chapter 2. DC Plasma Torches

    Czech Academy of Sciences Publication Activity Database

    Matveev, I.B.; Serbin, S.I.; Hrabovský, Milan

    Denver, Colorado: Outskirts Press, Incorporated, 2013 - (Matveev, I.), s. 130-182. (International Plasma Technology Center). ISBN 978-1-4327-8688-5 R&D Projects: GA ČR GAP205/11/2070 Institutional support: RVO:61389021 Keywords : plasma * combustion * gasification * Plasma Torches Subject RIV: BL - Plasma and Gas Discharge Physics

  16. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas

  17. On the Relativistic Quantum Plasma

    OpenAIRE

    Ahmad, Rashid; Ikramullah; Sharif, Saqib; Husain, Shakir; Khattak, Fida Younus

    2012-01-01

    Recently the interest in relativistic quantum plasma is increasing primarily to understand the fundamentals of the plasma behaviour and its properties. Mathematical models used to investigate these plasma are still need to be matured. Especially, the relativistic quantum electron-ion plasma are modeled using the Klein-Gordon equation and the Dirac equation for relativistic electrons. However, different properties of these plasma are investigated without anti-particles. We note that in order t...

  18. Adverse Effects of Plasma Transfusion

    OpenAIRE

    Pandey, Suchitra; Vyas, Girish N

    2012-01-01

    Plasma utilization has increased over the last two decades, and there is a growing concern that many plasma transfusions are inappropriate. Plasma transfusion is not without risk, and certain complications are more likely with plasma than other blood components. Clinical and laboratory investigations of the patients suffering reactions following infusion of fresh frozen plasma (FFP) define the etiology and pathogenesis of the panoply of adverse effects. We review here the pathogenesis, diagno...

  19. Plasma state. The universe's fire

    International Nuclear Information System (INIS)

    The plasma is the fourth state of matter, obtained at a very high temperature by the separation of the electrons from their nuclei. Plasma represents 99% of the visible mass of our present day universe and was the unique state of matter at its very beginning. Plasmas are present in the core of stars and in the interstellar environment. More closer to us, they are responsible of spectacular phenomena, like aurora borealis, lightning, comet queues etc.. This book makes a review of the different types of plasmas (electromagnetic, Earth's plasmas, spatial plasmas, solar plasmas, astrophysical plasmas). One chapter presents the thermonuclear fusion as future energy source. Another one treats of the chaos and turbulence inside plasmas. Some applications of plasmas are reviewed: MHD and ionic propulsion systems, MHD energy conversion and MHD generators, thermo-ionic converters, solid-state plasmas, particle accelerators, coherent radiation sources, 'Zeta' machines, X-ray lasers, isotopic separation, non-neutral plasmas and charged beams, free-electrons lasers, electrons and positrons plasmas, industrial applications (etching and cleaning, manufacturing of solar cells, flat screens, industrial reactors, waste treatment, cold plasma-assisted sterilization, effluents decontamination etc.). A last chapter makes an overview of the modern research in plasma physics. (J.S.)

  20. Surface-coatings by the plasma method - plasma spraying and plasma welding

    International Nuclear Information System (INIS)

    The present contribution gives a brief survey on surface coating according to the plasma method: plasma spraying and plasma welding. The spray material in plasma spraying (metal oxides and carbides) is introduced in powder-form into the plasma beam and sprayed onto the material. In plasma welding, the plasma is used as heat source and is electrically connected with the base material. The temperature thus increases and the layer (mostly cobalt, nickel or also copper base alloys) is welded to the base material. (GSCH)

  1. High Density Deuterium Plasma

    International Nuclear Information System (INIS)

    A dense plasma focus or foci are formed beyond the end of the inner electrode of a coaxial electrode discharge as a result of a strong pinch effect (Z pinch). Previous magnetic field distribution measurements lead to this conclusion. The plasma has the following interesting properties: (1) an electron temperature (from soft X-ray intensity ratios), ∼2 to 5 keV; (2) plasma volume (from soft X-ray pinhole images), 1 to 5 mm3; (3) time duration, ∼0.2 to 0.3 μsec; and (4) neutron yields, ∼5 x 107 cm/sec. Neutron production scales almost linearly with energy up to ∼ 36 kj (neutron yields ∼1011); the larger energies require initial gas pressures up to ∼6 Torr due to larger j x B forces. It is a curious fact that the maximum average sheath velocity in the annulus is limited to 7 cm/sec. Recent measurements using a small dc Bz field in the region of the plasma focus show indeed that the radial collapsing current sheath efficiently traps and compresses this field onto the axis. An analysis of the breech voltage and di/dt signals shows the expected behaviour of the tube inductance with time. The optimum focusing action of the current sheath occurs at peak current time when most of the condenser energy is still in storage; this energy is rapidly converted into plasma energy by the pinch forces ia a time ∼0.1 μsec (average collapse velocity Vc ∼ 4 x 107 cm/sec). A best fit to the bremsstrahlung (Z = 1) and neutron (assuming a thermonuclear plasma) data yields a plasma density of ∼ 2 to 3 x 1019 cm-3. One concludes that under some conditions the density may finally reach ∼ 1020 cm3. A calculation based on a collision-dominated plasma, according to the Bennett pinch relation for Te = Ti = 5 keV, r ∼0.05 cm, n∼2 x 1019 cm-3 requires a current of ∼7 x 105 A; at 20 kV, peak currents are∼8 x 105 A. The product of calculated density n and time τ gives nτ = 6 x 1012 sec cm-3. The plasma lifetime τ is >>τ(hydromagnetic); a preliminary calculation

  2. Optical plasma torch electron bunch generation in plasma wakefield accelerators

    Science.gov (United States)

    Wittig, G.; Karger, O.; Knetsch, A.; Xi, Y.; Deng, A.; Rosenzweig, J. B.; Bruhwiler, D. L.; Smith, J.; Manahan, G. G.; Sheng, Z.-M.; Jaroszynski, D. A.; Hidding, B.

    2015-08-01

    A novel, flexible method of witness electron bunch generation in plasma wakefield accelerators is described. A quasistationary plasma region is ignited by a focused laser pulse prior to the arrival of the plasma wave. This localized, shapeable optical plasma torch causes a strong distortion of the plasma blowout during passage of the electron driver bunch, leading to collective alteration of plasma electron trajectories and to controlled injection. This optically steered injection is more flexible and faster when compared to hydrodynamically controlled gas density transition injection methods.

  3. Nuclear excitation in plasma

    International Nuclear Information System (INIS)

    4 main electromagnetic excitation processes of atomic nuclei in hot dense plasma are reviewed: the black body photon absorption, the electron inelastic scattering, the nuclear excitation by electron capture (NEEC effect) and the nuclear excitation by electron transition (NEET effect). Experimental results on Ta181m are commented and an experiment showing the NEEC effect on Fe57 is described. A model including all the phenomena of excitation and de-excitation of a nuclear state in plasma, has been developed. Predictions about the evolution of the life-time of a nuclear excited state as a function of the temperature and density are made. A complete calculation of the NEET effect of the first excited state of U235 in a local thermodynamic equilibrium plasma is presented. Some experimental works on the excitation of U235m in a laser-produced plasma are discussed. The NEET effect on Hg201 in a laser-produced plasma is also considered in both theoretical and experimental aspects

  4. Plasma treatment of onychomycosis

    Science.gov (United States)

    Xiong, Zilan; Roe, Jeff; Grammer, Tim; Him, Yeon-Ho; Graves, David B.

    2015-09-01

    Onychomycosis or fungal infection of the toenail or fingernail is a common affliction. Approximately 10% of the world's adult population is estimated to suffer from onychomycosis. Current treatment options such as topical creams, oral drugs, or laser treatments are generally limited by a variety of problems. We present results for an alternative onychomycosis treatment scheme using atmospheric pressure cold air plasmas. Using thinned cow hoof as a model nail material, we tested the ability of various plasma sources to act through the model nail to eradicate either bacteria or fungus deposited on the opposite side. Following 20 minute exposure to a surface microdischarge (SMD) device operating in room air, we observed a ~ 2 log reduction of E. coli. A similar result was obtained against T. rubrum after 45 min plasma treatment. NOx species concentration penetrating through the model nail as well as uptake into the nail were measured as a function of nail thickness. We propose that these plasma-generated species, or perhaps their reaction products, are responsible for at least part of the observed anti-microbial effect. We also explore the use of ultraviolet light acting in synergy with plasma-generated chemical species.

  5. ITER plasma facing components

    International Nuclear Information System (INIS)

    This document summarizes results of the Conceptual Design Activities (1988-1990) for the International Thermonuclear Experimental Reactor (ITER) project, namely those that pertain to the plasma facing components of the reactor vessel, of which the main components are the first wall and the divertor plates. After an introduction and an executive summary, the principal functions of the plasma-facing components are delineated, i.e., (i) define the low-impurity region within which the plasma is produced, (ii) absorb the electromagnetic radiation and charged-particle flux from the plasma, and (iii) protect the blanket/shield components from the plasma. A list of critical design issues for the divertor plates and the first wall is given, followed by discussions of the divertor plate design (including the issues of material selection, erosion lifetime, design concepts, thermal and mechanical analysis, operating limits and overall lifetime, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, and advanced divertor concepts) and the first wall design (armor material and design, erosion lifetime, overall design concepts, thermal and mechanical analysis, lifetime and operating limits, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, an alternative first wall design, and the limiters used instead of the divertor plates during start-up). Refs, figs and tabs

  6. Mechanisms of Plasma Therapeutics

    Science.gov (United States)

    Graves, David

    2015-09-01

    In this talk, I address research directed towards biomedical applications of atmospheric pressure plasma such as sterilization, surgery, wound healing and anti-cancer therapy. The field has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that plasmas readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. It is postulated that cold atmospheric plasma (CAP) can trigger a therapeutic shielding response in tissue in part by creating a time- and space-localized, burst-like form of oxy-nitrosative stress on near-surface exposed cells through the flux of plasma-generated RONS. RONS-exposed surface layers of cells communicate to the deeper levels of tissue via a form of the ``bystander effect,'' similar to responses to other forms of cell stress. In this proposed model of CAP therapeutics, the plasma stimulates a cellular survival mechanism through which aerobic organisms shield themselves from infection and other challenges.

  7. Low Temperature Plasma Medicine

    Science.gov (United States)

    Graves, David

    2013-10-01

    Ionized gas plasmas near room temperature are used in a remarkable number of technological applications mainly because they are extraordinarily efficient at exploiting electrical power for useful chemical and material transformations near room temperature. In this tutorial address, I will focus on the newest area of low temperature ionized gas plasmas (LTP), in this case operating under atmospheric pressure conditions, in which the temperature-sensitive material is living tissue. LTP research directed towards biomedical applications such as sterilization, surgery, wound healing and anti-cancer therapy has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that LTP readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. I will review the evidence suggesting that RONS generated by plasmas are responsible for their observed therapeutic effects. Other possible bio-active mechanisms include electric fields, charges and photons. It is common in LTP applications that synergies between different mechanisms can play a role and I will review the evidence for synergies in plasma biomedicine. Finally, I will address the challenges and opportunities for plasma physicists to enter this novel, multidisciplinary field.

  8. Archimedes Plasma Mass Filter

    International Nuclear Information System (INIS)

    The Archimedes' Plasma Mass Filter is a novel plasma-based mass separation device. The basic physics of the Filter concept and a description of its primary application for nuclear waste separation at Hanford will be presented along with initial experimental results from a Demo device. The Demo is a 3.89 m long cylindrical device with a plasma radius of 0.4 m and an axial magnetic field up to 1600 Gauss. The plasma is produced by helicon waves launched by two four-strap antennas placed symmetrically either side of a central source region. One strap of each antenna is powered by one of four phase controlled 1 MW transmitters operating in the frequency range from 3.9 - 26 MHz. Each end of the device has ten concentric ring electrodes used to apply an electric field to rotate the plasma. Application of a parabolic voltage profile results in a rigid body rotation. Heavy ions above the cut-off mass number are extracted radially and collected by a heavy ion collector surrounding the source injection region while light ions are collected at the ends of the cylinder. Initial experiments will use noble gas and trace metals to demonstrate separation before attempting to operate with complex waste characteristic of Hanford

  9. Large area plasma source

    Science.gov (United States)

    Foster, John (Inventor); Patterson, Michael (Inventor)

    2008-01-01

    An all permanent magnet Electron Cyclotron Resonance, large diameter (e.g., 40 cm) plasma source suitable for ion/plasma processing or electric propulsion, is capable of producing uniform ion current densities at its exit plane at very low power (e.g., below 200 W), and is electrodeless to avoid sputtering or contamination issues. Microwave input power is efficiently coupled with an ionizing gas without using a dielectric microwave window and without developing a throat plasma by providing a ferromagnetic cylindrical chamber wall with a conical end narrowing to an axial entrance hole for microwaves supplied on-axis from an open-ended waveguide. Permanent magnet rings are attached inside the wall with alternating polarities against the wall. An entrance magnet ring surrounding the entrance hole has a ferromagnetic pole piece that extends into the chamber from the entrance hole to a continuing second face that extends radially across an inner pole of the entrance magnet ring.

  10. Photon kinetics in plasmas

    Directory of Open Access Journals (Sweden)

    V.G. Morozov

    2009-01-01

    Full Text Available We present a kinetic theory of radiative processes in many-component plasmas with relativistic electrons and nonrelativistic heavy particles. Using the non-equilibrium Green's function technique in many-particle QED, we show that the transverse field correlation functions can be naturally decomposed into sharply peaked (non-Lorentzian parts that describe resonant (propagating photons and off-shell parts corresponding to virtual photons in the medium. Analogous decompositions are obtained for the longitudinal field correlation functions and the correlation functions of relativistic electrons. We derive a kinetic equation for the resonant photons with a finite spectral width and show that the off-shell parts of the particle and field correlation functions are essential to calculate the local radiating power in plasmas and recover the results of vacuum QED. The plasma effects on radiative processes are discussed.

  11. Relativistic plasma dispersion functions

    Science.gov (United States)

    Robinson, P. A.

    1986-05-01

    The known properties of plasma dispersion functions (PDF's) for waves in weakly relativistic, magnetized, thermal plasmas are reviewed and a large number of new results are presented. The PDF's required for the description of waves with small wave number perpendicular to the magnetic field (Dnestrovskii and Shkarofsky functions) are considered in detail; these functions also arise in certain quantum electrodynamical calculations involving strongly magnetized plasmas. Series, asymptotic series, recursion relations, integral forms, derivatives, differential equations, and approximations for these functions are discussed as are their analytic properties and connections with standard transcendental functions. In addition a more general class of PDF's relevant to waves of arbitrary perpendicular wave number is introduced and a range of properties of these functions are derived.

  12. [Plasma properties: Annual report

    International Nuclear Information System (INIS)

    The Magneto-Fluid Dynamics Division of the Courant Institute is engaged in a broad program of basic research in the theoretical aspects of plasma physics and magneto-fluid dynamics with emphasis on those areas which are relevant to the fusion energy program. The total research program in the division includes efforts in the areas of plasma containment, stability, equilibrium, transport, wave propagation (including shock waves), heating, orbit theory, as well as numerical experiments and the development of practical numerical methods in all plasma problems. Applications are made to the following project areas: Tokamaks, Mirrors, Stellarators, and Alternate Concepts. Developments include the whole spectrum of models from macroscopic MHD and guiding center to Vlasov, drift kinetic Fokker-Planck, and Boltzmann. This document describes research completed as well as programs in progress

  13. Heating of toroidal plasmas

    International Nuclear Information System (INIS)

    The limitations of ohmic heating in achieving the thermonuclear ignition of a low-β toroidal plasma can be overcome by using several heating methods. Such methods are: fast neutral beam injection (possibly combined with an adiabatic compression or any other means) and HF heating, the most interesting schemes being based on plasma resonances. The basic physical phenomena in each method are briefly explained and results obtained are given. A new heating scheme using an outer frequency of a few kHz is described, that makes it possible to locate the exciting coils outside the vacuum vessel (some of these coils can be that producing the vertical magnetic field for the plasma equilibrium)

  14. Plasma rico en plaquetas Platelet -rich plasma

    Directory of Open Access Journals (Sweden)

    J. González Lagunas

    2006-04-01

    Full Text Available El Plasma Rico en Plaquetas es una suspensión concentrada de la sangre centrifugada que contiene elevadas concentraciones de trombocitos. Durante los últimos años, este producto ha aparecido de forma repetida en publicaciones científicas y en medios de comunicación generales como un producto que por sus características induce la curación y regeneración de los tejidos. La premisa de su uso es que las elevadas concentraciones de plaquetas en el PRP, liberan cantidades significativas de factores de crecimiento. En este artículo se van a recoger las evidencias científicas que se han presentado en la literatura médica con respecto al PRP y a la curación ósea, así como las diferentes aplicaciones clínicas que se han sugerido.Platelet-rich plasma is a by-product of centrifuged whole blood that contains high levels of thrombocytes. In the last decade, scientific and media interest has been generated by this product that apparently has the capacity of inducing and promoting tissue healing and regeneration. The premise of its use is that the large number of platelets in PRP release significant amounts of growth factors. In this paper, a critical review of the medical literature regarding PRP and bone healing will be presented. Also, the suggested clinical applications of the product will be addressed.

  15. The 2012 Plasma Roadmap

    International Nuclear Information System (INIS)

    Low-temperature plasma physics and technology are diverse and interdisciplinary fields. The plasma parameters can span many orders of magnitude and applications are found in quite different areas of daily life and industrial production. As a consequence, the trends in research, science and technology are difficult to follow and it is not easy to identify the major challenges of the field and their many sub-fields. Even for experts the road to the future is sometimes lost in the mist. Journal of Physics D: Applied Physics is addressing this need for clarity and thus providing guidance to the field by this special Review article, The 2012 Plasma Roadmap. Although roadmaps are common in the microelectronic industry and other fields of research and development, constructing a roadmap for the field of low-temperature plasmas is perhaps a unique undertaking. Realizing the difficulty of this task for any individual, the plasma section of the Journal of Physics D Board decided to meet the challenge of developing a roadmap through an unusual and novel concept. The roadmap was divided into 16 formalized short subsections each addressing a particular key topic. For each topic a renowned expert in the sub-field was invited to express his/her individual visions on the status, current and future challenges, and to identify advances in science and technology required to meet these challenges. Together these contributions form a detailed snapshot of the current state of the art which clearly shows the lifelines of the field and the challenges ahead. Novel technologies, fresh ideas and concepts, and new applications discussed by our authors demonstrate that the road to the future is wide and far reaching. We hope that this special plasma science and technology roadmap will provide guidance for colleagues, funding agencies and government institutions. If successful in doing so, the roadmap will be periodically updated to continue to help in guiding the field. (topical review)

  16. Laser induced plasma spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk; Kim, Nak Bae; Woo, Hyung Joo; Kim, Joon Kon; Kim, Gi Dong; Choi, Han Woo; Yoon, Yoon Yeol; Shim, Sang Kwun [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    When the pulsed laser is focused onto a small spot of a solid surface, an optically induced plasma is formed at this surface. This plasma will be formed when the laser power density exceeds the breakdown threshold value of the solid surface. The interaction of high power laser light with a target or solid materials have been an active topic not only in plasma physics but also in the field of analytical chemistry. Recently, LIPS(laser induced plasma spectroscopy) has been applied many kinds of sample analysis including solid, liquid and gas analysis. LIPS has a advantage of the minimal sample preparation required for a solid sample and ability to analyze conducting as well as nonconducting materials, multi-elemental analysis. But this method has a poorer sensitivity than several competing atomic spectroscopic methods and semiquantitative analysis. Numerous factors affect the ablation process, including the laser pulse properties, such as pulse width, spatial and temporal fluctuations of the pulse and laser power fluctuations. The mechanical, physical and chemical properties of the sample also influence the ablation process. We studied LIPS with Nd:YAG second harmonic 532 nm and the induced plasma temperature was studied by observing the emission intensity of Fe(I) line and the plasma temperature of the different kind of samples were calculated using Boltzmann plotting method under same laser condition. Using the above experimental results, LIPS has been applied for the analysis of the elemental distribution mapping of the polished rock section. For the elemental mapping analysis, XY stage controlled by step motor and PC were used and 5 x 5 mm element image was obtained. For the quantitative analysis, rock standard samples were analyzed and Ba, Cu, Fe, Mn, Si and Sr calibration curve were obtained. (author). 22 refs., 2 tabs., 14 figs.

  17. Plasma Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a

  18. Laser spectroscopy of thermal plasma

    International Nuclear Information System (INIS)

    Thermal plasma, due to its applications, is a research field of great importance, but reliable diagnostics of such plasma remains a challenging task. Spatially resolved methods, which provide local values of plasma parameters, are crucial for understanding the underlying physics. This can be achieved using pump–probe techniques. Two methods applicable and useful for thermal plasma diagnostics—four-wave mixing and scattering of laser beams—are discussed in this paper. Experimental examples of their application, namely four-wave mixing in argon arc plasma and scattering of laser light by laser-induced plasma, are presented. (paper)

  19. Railgun plasma armature characterisation experiments

    Science.gov (United States)

    Richardson, D. D.

    1984-05-01

    A plasma armature characterization experiment (PACE) is described. The PACE device is designed to study the plasma armature of railguns and yields information on properties such as temperature, pressure, densities, plasma potential, and ion species with their degrees of ionization. The main experimental studies are by spectroscopy of the light emitted and by Langmuir probes. The device simulates the plasma moving behind the projectile in a railgun by a static plasma held by electromagnetic forces against a fixed wall. Results to date demonstrate the feasibility of the concept and indicate improvements to the device which ensure that much useful information on railgun plasmas is forthcoming.

  20. Optical properties of cluster plasma

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Yasuaki; Tajima, Toshiki [Japan Atomic Energy Research Inst., Neyagawa, Osaka (Japan). Kansai Research Establishment; Downer, M.C.

    1998-03-01

    It is shown that unlike a gas plasma or an electron plasma in a metal, an ionized clustered material (`cluster plasma`) permits propagation below the plasma cut-off of electromagnetic (EM) waves whose phase velocity is close to but below the speed of light. This results from the excitation of a plasma oscillation mode (and/or polarization mode) through the cluster surface which does not exist in usual gaseous plasma. The existence of this new optical mode, cluster mode, is confirmed via numerical simulation. (author)

  1. Partial pressure analysis of plasmas

    International Nuclear Information System (INIS)

    The application of partial pressure analysis for plasma diagnostic measurements is reviewed. A comparison is made between the techniques of plasma flux analysis and partial pressure analysis for mass spectrometry of plasmas. Emphasis is given to the application of quadrupole mass spectrometers (QMS). The interface problems associated with the coupling of a QMS to a plasma device are discussed including: differential-pumping requirements, electromagnetic interferences from the plasma environment, the detection of surface-active species, ion source interactions, and calibration procedures. Example measurements are presented from process monitoring of glow discharge plasmas which are useful for cleaning and conditioning vacuum vessels

  2. Features of terrestrial plasma transport

    Science.gov (United States)

    Moore, T. E.; Chandler, M. O.; Chappell, C. R.; Pollock, C. J.; Waite, J. H., Jr.

    1989-01-01

    Research concerning the transport and distribution of ionospheric plasma in the magnetosphere are reviewed, stressing the dichotomy in explanations given for the low plasma densities outside the plasmasphere. The convection/hot solar plasma model and the convection/loss model are considered. Observations of global ionospheric outflows are compared with theoretical studies. It is suggested that there is a need for a hybrid model of magnetospheric plasma in which terrestrial plasma is both lost into the solar wind and energized and trapped within the magnetosphere, inflating the geomagnetic field and excluding cold plasma from conjugate regions.

  3. Plasma polarization spectroscopy

    CERN Document Server

    Iwamae, Atsushi

    2008-01-01

    Plasma Polarization Spectroscopy (PPS) is now becoming a standard diagnostic technique for working with laboratory plasmas. This new area needs a comprehensive framework, both experimental and theoretical. This book reviews the historical development of PPS, develops a general theoretical formulation to deal with this phenomenon, along with an overview of relevant cross sections, and reports on laboratory experiments so far performed. It also includes various facets that are interesting from this standpoint, e.g. X-ray lasers and effects of microwave irradiation. It also offers a timely discussion of instrumentation that is quite important in a practical PPS experiment.

  4. Plasma-wall interactions

    International Nuclear Information System (INIS)

    The plasma wall interactions for two extreme cases, the 'vacuum model' and the 'cold gas blanket' are outlined. As a first step for understanding the plasma wall interactions the elementary interaction processes at the first wall are identified. These are energetic ion and neutral particle trapping and release, ion and neutral backscattering, ion sputtering, desorption by ions, photons and electrons and evaporation. These processes have only recently been started to be investigated in the parameter range of interest for fusion research. The few measured data and their extrapolation into regions not yet investigated are reviewed

  5. Kinetics of complex plasmas

    CERN Document Server

    Sodha, Mahendra Singh

    2014-01-01

    The presentation in the book is based on charge balance on the dust particles, number and energy balance of the constituents and atom-ion-electron interaction in the gaseous plasma. Size distribution of dust particles, statistical mechanics, Quantum effects in electron emission from and accretion on dust particles and nonlinear interaction of complex plasmas with electric and electromagnetic fields have been discussed in the book. The book introduces the reader to basic concepts and typical applications. The book should be of use to researchers, engineers and graduate students.

  6. Theory of plasma electrodynamics

    International Nuclear Information System (INIS)

    The subject of this report is the physics of the electromagnetic behaviour of unmagnetized plasmas. After basic kinetic concepts, the dispersion relation of the plasma modes are developed, with emphasis on the comparison between the analytical expressions and the exact numerical solutions, especially on Landau dampings. Then, collisional dampings are presented. The mode couplings which drive parametric instabilities are then treated. Finally, the non-linear mechanisms, the pump depletion, designed as weak non-linearity, and the strong non-linearities which affect the longitudinal modes are discussed

  7. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

  8. Myopia and plasma cortisol.

    OpenAIRE

    Ojha R; Singh R; Maurya O; Agrawal J

    1989-01-01

    Estimation of plasma cortisol by fluorometric technique desorbed by Mallingly′s was carried out in 56 cases, including 38 cases of myopia (19 cases of simple myopia and 19 cases of degenerative myopia) and 18 normal individuals. Urinary 17-keto steroids/24 hours was also estimated by Zimmermann technique in 12 out of the 56 cases, which include 8 cases of myopia (4 cases of simple myopia and 4 cases of degenerative myopia) and 4 normal individuals as control. Plasma cortisol level is l...

  9. Dusty plasma in space

    Directory of Open Access Journals (Sweden)

    N. Kotsarenko

    1998-02-01

    Full Text Available Dusty plasmas consist of electrons, ions and charged dust particles observed in several astro-and space-physical environments such as nebulas, cometary tails, planetary rings, and planetary ionospheres. The presence of heavy, highly charged dust may significantly influence various physical processes, for example, the creation of spatial structures over a wide range of distances, from hundreds to tens of millions of kilometres. In this paper we present a review and an analysis of the spectra of volume and surface waves, instabilities and solitons in a dusty plasma.

  10. Plasma diagnostic reflectometry

    International Nuclear Information System (INIS)

    Theoretical and experimental studies of plasma diagnostic reflectometry have been undertaken as a collaborative research project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Plasma Diagnostics Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. Theoretical analyses have explored the basic principles of reflectometry to understand its limitations, to address specific gaps in the understanding of reflectometry measurements in laboratory experiments, and to explore extensions of reflectometry such as ultra-short-pulse reflectometry. The theory has supported basic laboratory reflectometry experiments where reflectometry measurements can be corroborated by independent diagnostic measurements

  11. Partially ionized plasmas including the third symposium on uranium plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, M. [ed.

    1976-09-01

    Separate abstracts are included for 28 papers on electrically generated plasmas, fission generated plasmas, nuclear pumped lasers, gaseous fuel reactor research, and applications. Five papers have been previously abstracted and included in ERA.

  12. Plasma detachment with molecular processes in divertor plasmas

    International Nuclear Information System (INIS)

    Molecular processes in detached recombining plasmas are briefly reviewed. Several reactions with vibrationally excited hydrogen molecule related to recombination processes are described. Experimental evidence of molecular activated recombination observed in a linear divertor plasma simulator is also shown. (author)

  13. Plasma flow in peripheral region of detached plasma in linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: hayashi-yuki13@ees.nagoya-u.ac.jp; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Kajita, S. [EcoTopia Science Institute, Nagoya University, Nagoya, Aichi 464-8603 (Japan); Tanaka, H. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

    2016-01-15

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.

  14. Plasma flow in peripheral region of detached plasma in linear plasma device

    International Nuclear Information System (INIS)

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front

  15. Plasma flow in peripheral region of detached plasma in linear plasma device

    Science.gov (United States)

    Hayashi, Y.; Ohno, N.; Kajita, S.; Tanaka, H.

    2016-01-01

    A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.

  16. Laser-plasma-based linear collider using hollow plasma channels

    Science.gov (United States)

    Schroeder, C. B.; Benedetti, C.; Esarey, E.; Leemans, W. P.

    2016-09-01

    A linear electron-positron collider based on laser-plasma accelerators using hollow plasma channels is considered. Laser propagation and energy depletion in the hollow channel is discussed, as well as the overall efficiency of the laser-plasma accelerator. Example parameters are presented for a 1-TeV and 3-TeV center-of-mass collider based on laser-plasma accelerators.

  17. Plasma heating power dissipation in low temperature hydrogen plasmas

    CERN Document Server

    Komppula, J

    2015-01-01

    Theoretical framework for power dissipation in low temperature plasmas in corona equilibrium is developed. The framework is based on fundamental conservation laws and reaction cross sections and is only weakly sensitive to plasma parameters, e.g. electron temperature and density. The theory is applied to low temperature atomic and molecular hydrogen laboratory plasmas for which the plasma heating power dissipation to photon emission, ionization and chemical potential is calculated. The calculated photon emission is compared to recent experimental results.

  18. Analogies between 'classical' plasmas and quark gluon plasma

    International Nuclear Information System (INIS)

    Using characterization methods specific to complex plasmas some information of the new state of the nuclear matter was reported by four major experiments from RHIC BNL (USA), namely the quark-gluon plasma. Additional arguments for the existence of the quark-gluon plasma in liquid phase is done. An equivalent Coulomb coupling parameter is used. Evidences for the liquid phase of the quark-gluon plasma are obtained, in agreement with the other experimental results. (author)

  19. Tokamak plasma self-organization-synergetics of magnetic trap plasmas

    NARCIS (Netherlands)

    Razumova, K. A.; Andreev, V. F.; Eliseev, L. G.; Kislov, A. Y.; La Haye, R. J.; Lysenko, S. E.; Melnikov, A. V.; Notkin, G. E.; Pavlov, Y. D.; Kantor, M. Y.

    2011-01-01

    Analysis of a wide range of experimental results in plasma magnetic confinement investigations shows that in most cases, plasmas are self-organized. In the tokamak case, it is realized in the self-consistent pressure profile, which permits the tokamak plasma to be macroscopically MHD stable. Existin

  20. Plasma rotation study in Tore Supra radio frequency heated plasmas

    International Nuclear Information System (INIS)

    Toroidal flows are found to improve the performance of the magnetic confinement devices with increase of the plasma stability and confinement. In ITER or future reactors, the torque from NBI should be less important than in present-day tokamaks. Consequently, it is of interest to study other intrinsic mechanisms that can give rise to plasma rotation in order to predict the rotation profile in experiments. Intriguing observations of plasmas rotation have been made in radio frequency (RF) heated plasmas with little or no external momentum injection. Toroidal rotation in both the direction of the plasma current (co-current) and in the opposite direction (counter-current) has been observed depending on the heating schemes and plasma performance. In Tore Supra, most observations in L-mode plasmas have been in the counter-current direction. However, in this thesis, we show that in lower hybrid current drive (LHCD), the core toroidal rotation increment is in co- or counter-current direction depending on the plasma current amplitude. At low plasma current the rotation change is in the co-current direction while at high plasma current, the change is in the counter-current direction. In both low and high plasma current cases, rotation increments are found to increase linearly with the injected LH power. Several mechanisms in competition which can induce co- or counter-current rotation in Tore Supra LHCD plasmas are investigated and typical order of magnitude are discussed in this thesis. (author)

  1. Modelling the Plasma Jet in Multi-Arc Plasma Spraying

    Science.gov (United States)

    Bobzin, K.; Öte, M.; Schein, J.; Zimmermann, S.; Möhwald, K.; Lummer, C.

    2016-08-01

    Particle in-flight characteristics in atmospheric plasma spraying process are determined by impulse and heat energy transferred between the plasma jet and injected powder particles. One of the important factors for the quality of the plasma-sprayed coatings is thus the distribution of plasma gas temperatures and velocities in plasma jet. Plasma jets generated by conventional single-arc plasma spraying systems and their interaction with powder particles were subject matter of intensive research. However, this does not apply to plasma jets generated by means of multi-arc plasma spraying systems yet. In this study, a numerical model has been developed which is designated to dealing with the flow characteristics of the plasma jet generated by means of a three-cathode spraying system. The upstream flow conditions, which were calculated using a priori conducted plasma generator simulations, have been coupled to the plasma jet simulations. The significances of the relevant numerical assumptions and aspects of the models are analyzed. The focus is placed on to the turbulence and diffusion/demixing modelling. A critical evaluation of the prediction power of the models is conducted by comparing the numerical results to the experimental results determined by means of emission spectroscopic computed tomography. It is evident that the numerical models exhibit a good accuracy for their intended use.

  2. Spectroscopic Diagnostic of Thermal Plasma Generated in DC Plasma Torch

    Czech Academy of Sciences Publication Activity Database

    Mašláni, Alan; Sember, Viktor

    Kudowa Zdroj, 2005. s. 24-25. [Fifth International Workshop and Summer School „Towards Fusion Energy – Plasma Physics, Diagnostics, Spin-offs“. 6.6.2005-10.6.2005, Kudowa Zdroj] Institutional research plan: CEZ:AV0Z20430508 Keywords : thermal plasma jet * optical emission spectroscopy * nonequilibrium Subject RIV: BL - Plasma and Gas Discharge Physics

  3. Plasma physics and instabilities

    International Nuclear Information System (INIS)

    These lectures procide an introduction to the theory of plasmas and their instabilities. Starting from the Bogoliubov, Born, Green, Kirkwood, and Yvon (BBGKY) hierarchy of kinetic equations, the additional concept of self-consistent fields leads to the fundamental Vlasov equation and hence to the warm two-fluid model and the one-fluid MHD, or cold, model. The properties of small-amplitude waves in magnetized (and unmagnetized) plasmas, and the instabilities to which they give rise, are described in some detail, and a complete chapter is devoted to Landau damping. The linear theory of plasma instabilities is illustrated by the current-driven electrostatic kind, with descriptions of the Penrose criterion and the energy principle of ideal MHD. There is a brief account of the application of feedback control. The non-linear theory is represented by three examples: quasi-linear velocity-space instabilities, three-wave instabilities, and the stability of an arbitrarily largeamplitude wave in a plasma. (orig.)

  4. Theoretical plasma physics

    International Nuclear Information System (INIS)

    This textbook which introduces plasma physics as a field of theoretical physics should be studied following the fundamental lectures of mechanics, electrodynamics, quantum theory, statistics and thermodynamics as a special field of students' education. It discusses the following topics: Motion of single particles (in a magnetic field, as drift in Hamilton theory); Equilibrium statistics of a plasma (cluster integrals, Debye-Hueckel theory of electron gas, Debye shielding and microfields); Kinetic plasma description (BBGKY hierarchy, Vlasov equation and Landau damping, Z-function, Landau-Fokker-Planck equation, Lenard-Balescu equation, Boltzmann equation and Lorentz collision term, driftkinetic equation); Macroscopic plasma description (moments, two-liquid-model, magnetohydrodynamics, magnetohydrostatics and hydromagnetic waves, the hydrodynamical regime, transport coefficients); Waves and instabilities in Vlasov systems (fundamentals, dispersion and instabilities in homogeneous systems, stationary inhomogeneous Vlasov systems, dispersion relations); Stability of magnetohydrodynamical systems (criteria of stability, applications of the energy principle, exchange instability, resistive instabilities); Nonlinear waves (wave breaking, ion-acoustic solitons, nonlinear Langmuir oscillations, the cubic nonlinear Schroedinger equation, drift vortices, BGK-modes); Integrability, chaos, and turbulence (integrability of the KdV-equation and the Schroedinger equation, collaps in NLS-systems and KdV systems, chaos in Schroedinger systems, weak turbulence); Appendix (system of units, Fourier and Laplace transformations, vectoranalytical relations). (orig.) With 58 figs

  5. Planetary plasmas and fields

    International Nuclear Information System (INIS)

    The magnetospheres of earth, Jupiter, and Mercury are discussed. The main features and physical processes characteristic of the quiet time earth magnetosphere are examined. Jupiter's larger and more distant magnetosphere is compared with the earth's and recent findings are reviewed. The plasma and field environment of Mercury is also discussed and similarities with the earth's magnetosphere are noted

  6. Filamentary magnetohydrodynamic plasmas

    International Nuclear Information System (INIS)

    A filamentary construct of magnetohydrodynamical plasma dynamics, based on the Elsasser variables was developed. This approach is modeled after discrete vortex models of hydrodynamical turbulence, which cannot be expected in general to produce results identical to ones based on a Fourier decomposition of the fields. In a highly intermittent plasma, the induction force is small compared to the convective motion, and when this force is neglected. the plasma vortex system is described by a Hamiltonian. For a system with many such vortices we present a statistical treatment of a collection of discrete current-vorticity concentrations. Canonical and microcanonical statistical calculations show that both the vorticity and the current spectra are peaked at long wavelengths, and the expected states revert to known hydrodynamical states as the magnetic field vanishes. These results differ from previous Fourier-based statistical theories. but it is found that when the filament calculation is expanded to include the inductive force, the results approach the Fourier equilibria in the low-temperature limit, and the previous Hamiltonian plasma vortex results in the high-temperature limit. Numerical simulations of a large number of filaments are carried out and support the theory. A three-dimensional vortex model is outlined as well, which is also Hamiltonian when the inductive force is neglected

  7. Quark gluon plasma

    Indian Academy of Sciences (India)

    C P Singh

    2000-04-01

    Recent trends in the research of quark gluon plasma (QGP) are surveyed and the current experimental and theoretical status regarding the properties and signals of QGP is reported. We hope that the experiments commencing at relativistic heavy-ion collider (RHIC) in 2000 will provide a glimpse of the QGP formation.

  8. Plasma-materials interactions

    International Nuclear Information System (INIS)

    Over the past year, plasma edge diagnostics for the Advanced Toroidal Facility were identified, and the design of hardware was initiated. These diagnostics are being prepared to study plasma density and temperature, particle and heat fluxes, impurity production and transport, and the configuration of the edge plasma. The conceptual design of top and bottom rail limiters, configured as calorimeter arrays, was finished, and detailed engineering design is under way. In collaboration with Japan and the Federal Republic of Germany, the PMI group is responsible for H/sub α/ measurements and the helium removal experiment on the ALT-II experiment in TEXTOR. Initial H/sub α/ measurements and calibration of the detectors were performed on TEXTOR. Several concepts have been investigated and the associated diagnostics identified to implement a helium removal experiment on ALT-II. In collaboration with France, a pump limiter system for steady-state operation is being designed for Tore Supra. In the past year, several concepts for pump limiter systems were studied, and predictive modeling of heat and particle removal was performed. Studies of plasma-surface phenomena were concentrated during the past year on graphites, wall carbonization, erosion/redeposition, and postmortem analysis of limiters. Erosion/redeposition experiments were performed with the 13C technique in collaboration with the JET and TEXTOR groups. Other initiatives include studies of surface effects on the performance of rf components

  9. Implicit plasma simulation

    International Nuclear Information System (INIS)

    Implicit time integration methods have been used extensively in numerical modelling of slowly varying phenomena in systems that also support rapid variation. Examples include diffusion, hydrodynamics and reaction kinetics. This article discussed implementation of implicit time integration in plasma codes of the ''particle-in-cell'' family, and the benefits to be gained

  10. Fundamentals of plasma physics

    CERN Document Server

    Bittencourt, J A

    1986-01-01

    A general introduction designed to present a comprehensive, logical and unified treatment of the fundamentals of plasma physics based on statistical kinetic theory. Its clarity and completeness make it suitable for self-learning and self-paced courses. Problems are included.

  11. Diamagnetism in a plasma

    International Nuclear Information System (INIS)

    This is an extension of a study of electric currents and force balance orthogonal to a unidirectional magnetic field of induction (B) in a collisionless plasma [K. D. Cole, Phys. Plasmas 3, 2717 (1996)]. All quantities are assumed to vary only in one direction orthogonal to B. Two new concepts are introduced, which are not in conventional plasma physics. First a magnetic polarization effect corresponding to electric polarization is found. This defines a contribution to the magnetic moment per unit volume of -ρmc2E2/B3. Second the conduction current is defined in terms of the curl of the magnetic field intensity H, in accordance with Maxwell. In this scheme, when there is no electric field, (1/4π)(∂H/∂z)B+(∂pperpendicular/∂z)=0, instead of the conventional equation with B/μ0 in place of H. In both schemes, jxB-∇pperpendicular=0. Though this makes no difference to the electric current intensity calculated in the two schemes, and no difference to the force balance equation, it makes a significant difference to the relationship between B and pperpendicular in many plasma conditions of interest. When the electric field is nonzero, the situation is more complex. It is shown that the new diamagnetism of this paper and the dielectric current of the earlier one are consistent with special relativity. Some applications of the theory are discussed. copyright 1997 American Institute of Physics

  12. Synthetic plasma ion source

    International Nuclear Information System (INIS)

    An improved crossed-beam charge-exchange ion gun in which a synthetic plasma is formed by injecting an electron beam into a collimated molecular beam just before the molecules are ionized by charge exchange with a crossed primary ion beam, thereby forming a secondary ion beam from the ionized but space-charge-neutralized and substantially undeflected molecular beam. The plasma thus formed extends to an aperture stop in an aperture tube which extends upstream from an anode downstream of which anode a cathode is placed. A field is formed within the cathode/anode space and within the aperture tube into which the plasma extends. The sheath edge of the plasma within the tube is curved by the field to form a meniscus, and the aperture, being smaller in area than the secondary ion beam upstream of the aperture, both collimates the secondary ion beam and acts as a lens stop for the subsequent immersion lens formed by the meniscus and the field region

  13. Theory of gas discharge plasma

    CERN Document Server

    Smirnov, Boris M

    2015-01-01

    This book presents the theory of gas discharge plasmas in a didactical way. It explains the processes in gas discharge plasmas. A gas discharge plasma is an ionized gas which is supported by an external electric field. Therefore its parameters are determined by processes in it. The properties of a gas discharge plasma depend on its gas component, types of external fields, their geometry and regimes of gas discharge. Fundamentals of a gas discharge plasma include elementary, radiative and transport processes which are included in its kinetics influence. They are represented in this book together with the analysis of simple gas discharges. These general principles are applied to stationary gas discharge plasmas of helium and argon. The analysis of such plasmas under certain conditions is theoretically determined by numerical plasma parameters for given regimes and conditions.

  14. A microwave plasma cleaning apparatus

    Science.gov (United States)

    Tsai, C. C.; Nelson, W. D.; Schechter, D. E.; Thompson, L. M.; Glover, A. L.

    1995-01-01

    In a microwave electron cyclotron resonance plasma source, reactive plasmas of oxygen and its mixtures of argon have been used for evaluating plasma cleaning technologies. Small aluminum samples (0.95 x 1.9 cm) were coated with thin films (less than or equal to 20 micrometers in thickness) of Shell Vitrea oil and cleaned with reactive plasmas. The discharge parameters, such as gas pressure, magnetic field, substrate biasing, and microwave power, were varied to change cleaning conditions. A mass spectroscopy (or residual gas analyzer) was used to monitor the status of plasma cleaning. Mass loss of the samples after plasma cleaning was measured to estimate cleaning rates. Measured cleaning rates of low-pressure (0.5-m torr) argon/oxygen plasmas were as high as 2.7 micrometers/min. X-ray photoelectron spectroscopy was used to determine cleanliness of the sample surfaces. In this paper, significant results of the plasma cleaning are reported and discussed.

  15. Fundamentals of Plasma Physics

    International Nuclear Information System (INIS)

    The widespread importance of plasmas in many areas of contemporary physics makes good textbooks in the field that are both introductory and comprehensive invaluable. This new book by Paul Bellen from CalTech by and large meets these goals. It covers the traditional textbook topics such as particle orbits, the derivation of the MHD equations from Vlasov theory, cold and warm plasma waves, Landau damping, as well as in the later chapters less common subjects such as magnetic helicity, nonlinear processes and dusty plasmas. The book is clearly written, neatly presented, and each chapter has a number of exercises or problems at their end. The author has also thankfully steered clear of the pitfall of filling the book with his own research results. The preface notes that the book is designed to provide an introduction to plasma physics for final year undergraduate and post-graduate students. However, it is difficult to see many physics undergraduates now at UK universities getting to grips with much of the content since their mathematics is not of a high enough standard. Students in Applied Mathematics departments would certainly fare better. An additional problem for the beginner is that some of the chapters do not lead the reader gently into a subject, but begin with quite advanced concepts. Being a multi-disciplinary subject, beginners tend to find plasma physics quite hard enough even when done simply. For postgraduate students these criticisms fade away and this book provides an excellent introduction. More senior researchers should also enjoy the book, especially Chapters 11-17 where more advanced topics are discussed. I found myself continually comparing the book with my favourite text for many years, 'The Physics of Plasmas' by T J M Boyd and J J Sanderson, reissued by Cambridge University Press in 2003. Researchers would want both books on their shelves, both for the different ways basic plasma physics is covered, and the diversity of more advanced topics. For

  16. Fundamentals of Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Cargill, P J [Imperial College School of Medicine (United Kingdom)

    2007-02-15

    The widespread importance of plasmas in many areas of contemporary physics makes good textbooks in the field that are both introductory and comprehensive invaluable. This new book by Paul Bellen from CalTech by and large meets these goals. It covers the traditional textbook topics such as particle orbits, the derivation of the MHD equations from Vlasov theory, cold and warm plasma waves, Landau damping, as well as in the later chapters less common subjects such as magnetic helicity, nonlinear processes and dusty plasmas. The book is clearly written, neatly presented, and each chapter has a number of exercises or problems at their end. The author has also thankfully steered clear of the pitfall of filling the book with his own research results. The preface notes that the book is designed to provide an introduction to plasma physics for final year undergraduate and post-graduate students. However, it is difficult to see many physics undergraduates now at UK universities getting to grips with much of the content since their mathematics is not of a high enough standard. Students in Applied Mathematics departments would certainly fare better. An additional problem for the beginner is that some of the chapters do not lead the reader gently into a subject, but begin with quite advanced concepts. Being a multi-disciplinary subject, beginners tend to find plasma physics quite hard enough even when done simply. For postgraduate students these criticisms fade away and this book provides an excellent introduction. More senior researchers should also enjoy the book, especially Chapters 11-17 where more advanced topics are discussed. I found myself continually comparing the book with my favourite text for many years, 'The Physics of Plasmas' by T J M Boyd and J J Sanderson, reissued by Cambridge University Press in 2003. Researchers would want both books on their shelves, both for the different ways basic plasma physics is covered, and the diversity of more advanced

  17. Thermal Plasma Gasification of Biomass

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Rijeka : InTech, 2011 - (Shahid Shaukat, S.), s. 39-62 ISBN 978-953-307-491-7 R&D Projects: GA ČR GAP205/11/2070 Institutional research plan: CEZ:AV0Z20430508 Keywords : thermal plasma * plasma gasification * biomass Subject RIV: BL - Plasma and Gas Discharge Physics http://www.intechopen.com/articles/show/title/thermal-plasma-gasification-of-biomass

  18. Controlled fusion and plasma heating

    International Nuclear Information System (INIS)

    The contributions presented in the 17th European Conference on Controlled Fusion and Plasma Heating were focused on Tore Supra investigations. The following subjects were presented: ohmic discharges, lower hybrid experiments, runaway electrons, Thomson scattering, plasma density measurements, magnetic fluctuations, polarization scattering, plasma currents, plasma fluctuation measurements, evaporation of hydrogen pellets in presence of fast electrons, ripple induced stochastic diffusion of trapped particles, tearing mode stabilization, edge effects on turbulence behavior, electron cyclotron heating, micro-tearing modes, divertors, limiters

  19. Stationary plasma accelerator - ATON engine

    International Nuclear Information System (INIS)

    The principles of a stationary plasma accelerator (engine) with closed electron drift are described. The accelerator has record integral characteristics. A method for analysis of operating process features in the integral characteristics is proposed. Results are presented of local measurements of the plasma parameters in the accelerator channel and in the leaving plasma jet Main attention is paid to determination of the part of twice ionized ions in the plasma flow

  20. Wakes in Inertial Fusion Plasmas

    OpenAIRE

    Ellis, Ian Norman

    2014-01-01

    Plasma wave wakes, which are the collective oscillatory response near the plasma frequency to the propagation of particles or electromagnetic waves through a plasma, play a critical role in many plasma processes. New results from backwards stimulated Raman scattering (BSRS), in which wakes with phase velocities much less than the speed of light are induced by the beating of counter-propagating light waves, and from electron beam stopping, in which the wakes are produced by the motion of relat...

  1. Tomographic diagnostics of nonthermal plasmas

    Science.gov (United States)

    Denisova, Natalia

    2009-10-01

    In the previous work [1], we discussed a ``technology'' of tomographic method and relations between the tomographic diagnostics in thermal (equilibrium) and nonthermal (nonequilibrium) plasma sources. The conclusion has been made that tomographic reconstruction in thermal plasma sources is the standard procedure at present, which can provide much useful information on the plasma structure and its evolution in time, while the tomographic reconstruction of nonthermal plasma has a great potential at making a contribution to understanding the fundamental problem of substance behavior in strongly nonequilibrium conditions. Using medical terminology, one could say, that tomographic diagnostics of the equilibrium plasma sources studies their ``anatomic'' structure, while reconstruction of the nonequilibrium plasma is similar to the ``physiological'' examination: it is directed to study the physical mechanisms and processes. The present work is focused on nonthermal plasma research. The tomographic diagnostics is directed to study spatial structures formed in the gas discharge plasmas under the influence of electrical and gravitational fields. The ways of plasma ``self-organization'' in changing and extreme conditions are analyzed. The analysis has been made using some examples from our practical tomographic diagnostics of nonthermal plasma sources, such as low-pressure capacitive and inductive discharges. [0pt] [1] Denisova N. Plasma diagnostics using computed tomography method // IEEE Trans. Plasma Sci. 2009 37 4 502.

  2. High-temperature plasma physics

    International Nuclear Information System (INIS)

    Both magnetic and inertial confinement research are entering the plasma parameter range of fusion reactor interest. This paper reviews the individual and common technical problems of these two approaches to the generation of thermonuclear plasmas, and describes some related applications of high-temperature plasma physics

  3. Optical properties of dense plasmas

    International Nuclear Information System (INIS)

    The following topics were dealt with: Stellar spectra and stellar atmospheres, spectrocopic methods in the plasma diagnostic, Green function method, influence of charged plasma particles on the line profile, Storer-Strahler interaction, dynamic screening effects, line profile shift and asymmetry, collective plasma excitations, ion dynamic effects on line profiles

  4. Elements of plasma kinetic theory

    International Nuclear Information System (INIS)

    The physical foundations of plasma kinetic equations are exposed inside a series of seminars on plasma and fusion physics. The Vlasov and collisional equations with its application range have been discussed. The momenta equations for the macroscopic magnitudes and the more usual approximations have been obtained: two fluid equations for cold and warm plasmas, magnetohydrodynamic equations and the double-adiabatic theory. (author)

  5. Plasma pyrolysis of toxic waste

    Science.gov (United States)

    Rutberg, Ph G.

    2003-06-01

    The comparison of technical economic indexes of different waste treatment methods and plasma pyrolysis is presented in the paper. It testifies that plasma technologies are economically expedient for these purposes. Physical prerequisites allowing realizing plasma technologies are presented. Reliable and economical (70-120 Euro per ton of treated product) plasma generation is the basic condition of the technology realization. In this connection, various types of powerful generators of dense plasma (plasmatrons) in the range from 100 kW to 3 MW and temperature of plasma jets from 2000 to 10 000 K, and also physical processes taking place in electric-discharge chambers are examined. Differences between AC and DC electric arc plasma generators are analysed. Temperature in arcs of plasma generators varies from 6000 to 20 000 K, electron concentration is ne~(1014-1019 cm-3). Specific ware of electrodes in various types of plasma generators intended for long-time operation modes is (10-7-10-4) g C-1. Physicochemical processes in plasma reactors intended for waste treatment and pyrolysis are described. Different types of technological processes on plasma treatment and pyrolysis of waste are analysed. Estimation of present situation of physical investigations and technological developments in this area and predictions for nearest future are included. This article was scheduled to appear in issue 5 of Plasma Phys. Control. Fusion. To access this Special issue please follow this link: http://www.iop.org/EJ/toc/0741-3335/45/5

  6. Diagnostics of planetary nebulae plasma

    International Nuclear Information System (INIS)

    Starting with the pioneering Ambartsumian's papers, the problems of diagnostics of low density plasma of planetary nebulae are reviewed. We discuss both the early papers of Ambartsumian and the papers developing the methods of plasma diagnostics based on Ambartsumian's ideas. The diagnostics methods for both homogeneous and inhomogeneous nebular plasma are described

  7. Numerical simulation of dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Winske, D.

    1995-09-01

    The numerical simulation of physical processes in dusty plasmas is reviewed, with emphasis on recent results and unresolved issues. Three areas of research are discussed: grain charging, weak dust-plasma interactions, and strong dust-plasma interactions. For each area, we review the basic concepts that are tested by simulations, present some appropriate examples, and examine numerical issues associated with extending present work.

  8. Miniature Coaxial Plasma injector Diagnostics by Beam Plasma Interaction

    International Nuclear Information System (INIS)

    A miniature coaxial gun has been used to study the interaction between plasma beam and low density plasma formed in glow discharge. The peak discharge current flow between the coaxial electrodes was 5.25 kA as a single pulse with pulse width of 60 mu. Investigations are carried out with argon gas at pressure 0.4 Torr. The plasma stream ejected from the coaxial discharge propagates in the neutral argon atoms with mean velocity of 1.2x105cm/s. The plasma stream temperature and density were 4.2 eV and 2.4x1013 cm-3respectively. An argon negative glow has been used as base plasma where its electron temperature and density were 2.2 eV and 6.2x107 cm-3 respectively. When the plasma stream propagates through the negative glow discharge region its velocity decreased to 8.8 x 104 cm/s and also the plasma electron temperature decreased to 3.1 eV, while the stream density remained the same. An excited wave appeared on the electric probe having frequency equal to the plasma frequency of the plasma under consideration. Simulation of the problem showed that this method could be applied for plasma diagnostics within the region of investigation. Those further studies for high temperature, dense, and magnetized plasma will be considered

  9. MHD Simulations of Thermal Plasma Jets in Coaxial Plasma Accelerators

    Science.gov (United States)

    Subramaniam, Vivek; Raja, Laxminarayan

    2015-09-01

    The development of a magneto-hydrodynamics (MHD) numerical tool to study high energy density thermal plasma in coaxial plasma accelerators is presented. The coaxial plasma accelerator is a device used simulate the conditions created at the confining wall of a thermonuclear fusion reactor during an edge localized mode (ELM) disruption event. This is achieved by creating magnetized thermal plasma in a coaxial volume which is then accelerated by the Lorentz force to form a high velocity plasma jet. The simulation tool developed solves the resistive MHD equation using a finite volume method (FVM) framework. The acceleration and subsequent demagnetization of the plasma as it travels down the length of the accelerator is simulated and shows good agreement with experiments. Additionally, a model to study the thermalization of the plasma at the inlet is being developed in order to give self-consistent initial conditions to the MHD solver.

  10. The Plasma Chemistry of Polymer Surfaces

    CERN Document Server

    Friedrich, Jö

    2012-01-01

    This book illustrates plasma properties, polymer characteristics, surface specifics, and how to purposefully combine plasma and polymer chemistry. In so doing, it covers plasma polymerization, surface functionalization, etching, crosslinking, and deposition of monotype functional-group-bearing plasma polymers. It explains different techniques and plasma types, such as pressure-pulsed, remote, low-wattage plasmas and plasma polymerization in liquids. Finally, among the numerous applications discussed are plasmas for chemical synthesis, industrial processes or the modification of membranes and p

  11. Experimental Plasma Research project summaries

    International Nuclear Information System (INIS)

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report

  12. Tecnical report- Group of Plasma

    International Nuclear Information System (INIS)

    The research activities of Plasma Laboratory at UNICAMP (University of Campinas, Brazil) in the period from november 84 to july/85 are described. In the TUPA project, several works related to substructure and research programs were developed. Diagnostic techniques to analyse the theta Pinch implosion phase, a presure probe, an electrostatic ion energy analyser and laser-produced plasma spectroscopy were developed. The experimental results were obtained, using multiple magnetic probes inserted in the plasma. These results were analysed by numerical code using some MHD equations in 2 dimensions. A description of plasma dynamic was determined and the plasma parameters such as density and temperature were estimated. (M.C.K.)

  13. Experimental Plasma Research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  14. Experimental plasma research project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1978-08-01

    This report contans descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Measurements and Instrumentation; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  15. Waves and Oscillations in Plasmas

    CERN Document Server

    Pecseli, Hans L

    2012-01-01

    The result of more than 15 years of lectures in plasma sciences presented at universities in Denmark, Norway, and the United States, Waves and Oscillations in Plasmas addresses central issues in modern plasma sciences. The book covers fluid models as well as kinetic plasma models, including a detailed discussion of, for instance, collisionless Landau damping. Offering a clear separation of linear and nonlinear models, the book can be tailored for readers of varying levels of expertise.Designed to provide basic training in linear as well as nonlinear plasma dynamics, and practical in areas as d

  16. Experimental plasma research project summaries

    International Nuclear Information System (INIS)

    This report contans descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Measurements and Instrumentation; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report

  17. Transport processes in space plasmas

    International Nuclear Information System (INIS)

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth's magnetosphere and associated waves, the Earth's magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth's magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior

  18. Plasma pyrolysis of toxic waste

    International Nuclear Information System (INIS)

    The comparison of technical economic indexes of different waste treatment methods and plasma pyrolysis is presented in the paper. It testifies that plasma technologies are economically expedient for these purposes. Physical prerequisites allowing realizing plasma technologies are presented. Reliable and economical (70-120 Euro per ton of treated product) plasma generation is the basic condition of the technology realization. In this connection, various types of powerful generators of dense plasma (plasmatrons) in the range from 100 kW to 3 MW and temperature of plasma jets from 2000 to 10 000 K, and also physical processes taking place in electric-discharge chambers are examined. Differences between AC and DC electric arc plasma generators are analysed. Temperature in arcs of plasma generators varies from 6000 to 20,000 K, electron concentration is ne ∼ (1014-1019 cm-3). Specific ware of electrodes in various types of plasma generators intended for long-time operation modes is (10-7-10-4) g C-1. Physicochemical processes in plasma reactors intended for waste treatment and pyrolysis are described. Different types of technological processes on plasma treatment and pyrolysis of waste are analysed. Estimation of present situation of physical investigations and technological developments in this area and predictions for nearest future are included

  19. Adiabatic plasma buncher

    International Nuclear Information System (INIS)

    In this paper is presented a new scheme of injection into a plasma accelerator, aimed at producing a high quality beam while relaxing the demands on the bunch length of the injected beam. The beam dynamics in the injector, consisting of a high voltage pulsed photo-diode, is analyzed and optimized to produce a λp/20 long electron bunch at 2.5 MeV. This bunch is injected into a plasma wave in which it compresses down to λp/100 while simultaneously accelerating up to 250 MeV. This simultaneous bunching and acceleration of a high quality beam requires a proper combination of injection energy and injection phase. Preliminary results from simulations are shown to assess the potentials of the scheme

  20. Ion plasma electron gun

    International Nuclear Information System (INIS)

    In the disclosed electron gun positive ions generated by a hollow cathode plasma discharge in a first chamber are accelerated through control and shield grids into a second chamber containing a high voltage cold cathode. These positive ions bombard a surface of the cathode causing the cathode to emit secondary electrons which form an electron beam having a distribution adjacent to the cathode emissive surface substantially the same as the distribution of the ion beam impinging upon the cathode. After passing through the grids and the plasma discharge chamber, the electron beam exits from the electron gun via a foil window. Control of the generated electron beam is achieved by applying a relatively low control voltage between the control grid and the electron gun housing (which resides at ground potential) to control the density of the positive ions bombarding the cathode

  1. Microstructured plasma sources

    Energy Technology Data Exchange (ETDEWEB)

    Buettgenbach, S.; Lucas, N.; Sichler, P. [Institut fuer Mikrotechnik, Technische Universitaet Braunschweig (Germany)

    2009-10-15

    Dielectric barrier discharges generated in microcavities or by the use of microstructures have gained increasing interest in research and industry in recent years. This is due to the advantages of small dimensions of microstructured plasma sources and particularly their ability to generate plasmas at atmospheric pressure. In the scope of this work the design and fabrication of two different microplasma sources is presented. First, microplasma reactors based on microstructured electrode arrays which have detailed dimensions in the range of some tens of micrometers and have been successfully applied for the decomposition of waste gases are presented. Subsequently microplasma stamps, which allow the generation of microplasmas in closed cavities and which are powerful process tools for area-selective modification of various surfaces at atmospheric pressure, are presented. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Neutrino beam plasma instability

    Indian Academy of Sciences (India)

    Vishnu M Bannur

    2001-10-01

    We derive relativistic fluid set of equations for neutrinos and electrons from relativistic Vlasov equations with Fermi weak interaction force. Using these fluid equations, we obtain a dispersion relation describing neutrino beam plasma instability, which is little different from normal dispersion relation of streaming instability. It contains new, nonelectromagnetic, neutrino-plasma (or electroweak) stable and unstable modes also. The growth of the instability is weak for the highly relativistic neutrino flux, but becomes stronger for weakly relativistic neutrino flux in the case of parameters appropriate to the early universe and supernova explosions. However, this mode is dominant only for the beam velocity greater than 0.25 and in the other limit electroweak unstable mode takes over.

  3. Magnetospheric plasma physics

    International Nuclear Information System (INIS)

    The discovery of the earth's radiation belts in 1957 by Van Allen marked the beginning of what is now known as magnetospheric physics. In this study of plasma physics in the magnetosphere, we shall take the magnetosphere to be that part of the earth's ionized atmosphere which is formed by the interaction of the solar wind with the earth's dipole-like magnetic field. It extends from approximately 100km above the earth's surface where the proton-neutral atom collision frequency is equal to the proton gyrofrequency to about ten earth radii (RE ∼ 6380km) in the sunward direction and to several hundred earth radii in the anti-sunward direction. The collision dominated region is called the ionosphere and is sometimes considered separate from the collisionless plasma region. In the ionosphere ion-neutral collisions are dominant and one may think of the ionosphere as a frictional boundary layer ∼ 1000km thick. Other planets are also considered. (author)

  4. Relativistic spherical plasma waves

    CERN Document Server

    Bulanov, S S; Schroeder, C B; Zhidkov, A G; Esarey, E; Leemans, W P

    2011-01-01

    Tightly focused laser pulses as they diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we report on theoretical study of relativistic spherical wake waves and their properties, including wave breaking. These waves may be suitable as particle injectors or as flying mirrors that both reflect and focus radiation, enabling unique X-ray sources and nonlinear QED phenomena.

  5. Plasma antioxidants from chocolate

    OpenAIRE

    Serafini, M.; Bugianesi, R.; Maiani, G; Valtuena, S.; De Santis, S.; Crozier, A.

    2003-01-01

    There is some speculation that dietary flavonoids from chocolate, in particular (-)epicatechin, may promote cardiovascular health as a result of direct antioxidant effects or through antithrombotic mechanisms. Here we show that consumption of plain, dark chocolate results in an increase in both the total antioxidant capacity and the (-)epicatechin content of blood plasma, but that these effects are markedly reduced when the chocolate is consumed with milk or if milk is incorporated as milk ch...

  6. Plasma cell vulvitis

    Directory of Open Access Journals (Sweden)

    Pravin R Bharatia

    2015-01-01

    Full Text Available Plasma cell vulvitis is a very rare inflammatory disorder of vulva, characterized by a bright-red mucosal lesion of significant chronicity, which may be symptomatic. Very few case studies of this condition are reported in literature. We describe one such classical patient, who presented with slight dyspareunia. The diagnosis was confirmed on histopathological examination. It is important for clinicians to accurately diagnose this alarming condition in time.

  7. Princeton Plasma Physics Laboratory:

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, C.A. (ed.)

    1986-01-01

    This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations.

  8. Princeton Plasma Physics Laboratory:

    International Nuclear Information System (INIS)

    This paper discusses progress on experiments at the Princeton Plasma Physics Laboratory. The projects and areas discussed are: Principal Parameters Achieved in Experimental Devices, Tokamak Fusion Test Reactor, Princeton Large Torus, Princeton Beta Experiment, S-1 Spheromak, Current-Drive Experiment, X-ray Laser Studies, Theoretical Division, Tokamak Modeling, Spacecraft Glow Experiment, Compact Ignition Tokamak, Engineering Department, Project Planning and Safety Office, Quality Assurance and Reliability, and Administrative Operations

  9. Laser plasma accelerators

    OpenAIRE

    Malka, V.

    2012-01-01

    Research activities on laser plasma accelerators are paved by many significant breakthroughs. This review article provides an opportunity to show the incredible evolution of this field of research which has, in record time, allowed physicists to produce high quality electron beams at the GeV level using compact laser systems. I will show the scientific path that led us to explore different injection schemes and to produce stable, high peak current and high quality electron beams with control ...

  10. Plasma Sprayed Resistors

    OpenAIRE

    Anderson, J. C.; Smith, D. P. H.

    1980-01-01

    A range of films of mixed composition, prepared by arc plasma spraying, has been investigated. Both free powder and powder in a plastic binder forming a rod have been used in the spray process. A variety of mixtures of insulators, metals and semiconductors has been examined and it is shown that resistivity/temperature curves for the specimens produced have in general two points of inflection, the temperatures of which vary with composition. This allows prediction of a composition giving low T...

  11. Argon plasma coagulation

    Directory of Open Access Journals (Sweden)

    Zenker, Matthias

    2008-03-01

    Full Text Available Argon Plasma Coagulation (APC is an application of gas discharges in argon in electrosurgery, which is increasingly used especially in endoscopy. The major application fields are haemostasis, tissue devitalization and tissue reduction.This review describes the physics and technology of electrosurgery and APC. Some characteristics of the argon discharge are shown and discussed, and thermal effects in biological tissue are described. Subsequently, examples of medical applications are given.

  12. Dusty plasma in space

    OpenAIRE

    N. Ya. Kotsarenko; S. V. Koshevaya; A. N. Kotsarenko

    1998-01-01

    Dusty plasmas consist of electrons, ions and charged dust particles observed in several astro-and space-physical environments such as nebulas, cometary tails, planetary rings, and planetary ionospheres. The presence of heavy, highly charged dust may significantly influence various physical processes, for example, the creation of spatial structures over a wide range of distances, from hundreds to tens of millions of kilometres. In this paper we present a review and an analysis of the spectra o...

  13. Dense Plasma Focus Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Shengtai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jungman, Gerard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes-Sterbenz, Anna Catherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-31

    The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

  14. New Aspects of Plasma Physics

    Science.gov (United States)

    Schukla, Padma K.; Stenflo, Lennart; Eliasson, Bengt

    2008-03-01

    Nonlinear collective processes in very dense plasmas / P. K. Shukla, B. Eliasson and D. Shaikh -- Quantum, spin and QED effects in plasmas / G. Brodin and M. Marklund -- Spin quantum plasmas - new aspects of collective dynamics / M. Marklund and G. Brodin -- Revised quantum electrodynamics with fundamental applications / B. Lehnert -- Quantum methodologies in beam, fluid and plasma physics / R. Fedele -- Plasma effects in cold atom physics / J. T. Mendonca ... [et al.] -- General properties of the Rayleigh-Taylor instability in different plasma configurations: the plasma foil model / F. Pegoraro and S. V. Bulanov -- The Rayleigh-Taylor instability of a plasma foil accelerated by the radiation pressure of an ultra intense laser pulse / F. Pegoraro and S. V. Bulanov -- Generation of galactic seed magnetic fields / H. Saleem -- Nonlinear dynamics of mirror waves in non-Maxwellian plasmas / O. A. Pokhotelov et al. -- Formation of mirror structures near instability threshold / E. A. Kuznetsov, T. Passot and P. L. Sulem -- Nonlinear dispersive Alfvén waves in magnetoplasmas / P. K. Shukla ... [et al.] -- Properties of drift and Alfvén waves in collisional plasmas / J. Vranjes, S. Poedts and B. P. Pandey -- Current driven acoustic perturbations in partially ionized collisional plasmas / J. Vranjes ... [et al.] -- Multifluid theory of solitons / F. Verheest -- Nonlinear wavepackets in pair-ion and electron-positron-ion plasmas / I. Kourakis et al. -- Electro-acoustic solitary waves in dusty plasmas / A. A. Mamun and P. K. Shukla -- Physics of dust in magnetic fusion devices / Z. Wang et al. -- Short wavelength ballooning mode in Tokamaks / A. Hirose and N. Joiner -- Effects of perpendicular shear superposition and hybrid ions intruduction on parallel shear driven plasma instabilities / T. Kaneko and R. Hatakeyama.

  15. The Coalition for Plasma Science: Bringing Plasmas to the Public

    Science.gov (United States)

    Berry, Lee

    2003-10-01

    The Coalition for Plasma Science is a group of institutions, organizations, and companies that have joined forces to increase awareness and understanding of plasma science and its many applications and benefits for society. The CPS undertakes a range of activities to support this goal. Members include national laboratories, universities, industries, and individuals. The CPS maintains a web page (http://www.plasmacoalition.org), and has developed several types of plasma-related publications. The web page includes a compilation of evaluated plasma web sites. The evaluations were conducted by teachers and based on national teaching standards. The web site also contains copies of CPS publications including the brochure ''Plasmas are Everywhere.'' Thousands of these brochures are distributed each year, and a poster version is now available. Another publication is the ''About Plasmas'' series. Each of these two-page papers (which is written for a general audience) is about a specific plasma-related topic, such as lighting, fusion, space plasmas and plasma decontamination of biological hazards. Papers on other topics are under development. The CPS also organizes educational luncheon/seminars for Members of Congress and their staff. The most recent seminar was given by David Newman on January 28th of this year and was his ''state of the universe'' address. A second seminar is planned this year on the topic of semiconductor manufacturing. Activities under discussion include a topical science fair award for a project on plasmas and the development of a broad, history-based educational web site.

  16. Linking plasma kinetics to plasma-bio interactions

    Science.gov (United States)

    Bruggeman, Peter

    2015-05-01

    Cold non-equilibrium atmospheric pressure plasmas have received a lot of attention in the last decade due to their huge potential for biomedical applications. In my group, we have characterized an RF driven APPJ in great detail. The characterization includes electrical measurements, imaging, optical emission spectroscopy, (two photon enhanced) laser induced fluorescence, Thomson scattering, Rayleigh scattering, Raman scattering and mass spectrometry. This led to a detailed knowledge of the electron density, electron temperature, gas temperature, NO, O, OH, O3 densities, ionic species and air concentrations in the plasma effluent. Living organisms for in vitro studies are typically kept in complex solutions or culture media. Plasma-bio interactions involves not only the production of reactive species in the plasma gas phase but also transport to the liquid phase and plasma induced liquid phase chemistry and its impact on the living organisms. Reactive nitrogen and oxygen species have been identified as the key reactive species. Recent results of my group show that controlling the gas phase plasma chemistry can lead to significant different biological responses of the living organisms corresponding to different chemical pathways. The effect of plasma jet interaction with liquids containing mammalian cells, bacteria and virus will be discussed. The outcomes of these studies allow unraveling chemical pathways responsible for plasma-bio interactions and linking plasma kinetics to plasma-bio interactions.

  17. Plasma theory and computation

    International Nuclear Information System (INIS)

    Progress in this area is reported in five sections: (1) Magnetohydrodynamic theory. The nonlinear behavior of MHD instabilities to tokamaks was studied numerically. Linear stability was also investigated, using combinations of exact and approximate methods. Two-dimensional tokamak equilibrium codes were used to ascertain the effect of an iron core transformer, and a three-dimensional equilibrium code was developed to study finite beta effects in the ELMO Bumpy Torus. (2) Kinetic theory. Numerical methods were derived to solve the drift kinetic equation, initially to study neoclassical diffusion and dissipative trapped electron instabilities in tokamaks. A parallel effort has extended the linear theory of these instabilities into experimentally relevant regimes and derived shear stabilization criteria for them. The theory of neutral beam injection into tokamaks was expanded and compared successfully with experiment. Finite-beta and electric-field effects on particle orbits in the EBT were studied. (3) Plasma modeling. One-dimensional tokamak transport codes were improved and used to study neutral beam injection and impurity effects. (4) Plasma engineering. Plasma characteristics required for break-even conditions in F-BX and TCT were determined. Prospects for burning advanced fuels such as D-D and D-6Li were studied. The power balance in EBT was studied, using a zero-dimensional point model. (5) Data handling. The ORMAK data system was improved, and initial work on the EBT system was completed. (U.S.)

  18. Radially inhomogeneous bounded plasmas

    Science.gov (United States)

    Zakeri-Khatir, H.; Aghamir, F. M.

    2016-07-01

    On the basis of kinetic theory along with self-consistent field equations, the expressions for dielectric tensor of radially inhomogeneous magnetized plasma columns are obtained. The study of dielectric tensor characteristics allows the accurate analysis of the inhomogeneous properties, beyond limitations that exist in the conventional method. Through the Bessel–Fourier transformation, the localized form of material equations in a radially inhomogeneous medium are obtained. In order to verify the integrity of the model and reveal the effect of inhomogeneity, a special case of a cylindrical plasma waveguide completely filled with inhomogeneous magnetized cold plasma was considered. The dispersion relation curves for four families of electromagnetic (EH and HE) and electrostatic (SC and C) modes are obtained and compared with the findings of the conventional model. The numerical analysis indicates that the inhomogeneity effect leads to coupling of electromagnetic and electrostatic modes each having different radial eigen numbers. The study also reveals that the electrostatic modes are more sensitive to inhomogeneous effects than the electromagnetic modes.

  19. Plasma Modeling of Electrosurgery

    Science.gov (United States)

    Jensen, Scott; Friedrichs, Daniel; Gilbert, James; Park, Wounjhang; Maksimovic, Dragan

    2014-10-01

    Electrosurgery is the use of high frequency alternating current (AC) to illicit a clinical response in tissue, such as cutting or cauterization. Power electronics converters have been demonstrated to generate the necessary output voltage and current for electrosurgery. The design goal of the converter is to regulate output power while supplying high frequency AC. The design is complicated by fast current and voltage transients that occur when the current travels through air in the form of an arc. To assist in designing a converter that maintains the desired output power during these transients, we have used the COMSOL Plasma Module to determine the output voltage and current characteristics during an arc. This plasma model, used in conjunction with linear circuit elements, allows the full electrosurgical system to be validated. Two models have been tested with the COMSOL Plasma Module. One is a four-species, four-reaction model based on the local field approximation technique. The second simulates the underlying air chemistry using 30 species, 151 chemical reactions, and a coupled electron energy distribution function. Experimental output voltage and current samples have been collected and compared to both models.

  20. Microwave Argon Plasma Torch

    Science.gov (United States)

    Felizardo, Edgar; Pencheva, Mariana; Benova, Evgenia; Dias, Fransisco; Tatarova, Elena

    2009-10-01

    A theoretical and experimental investigation of a microwave (2.45 GHz) Argon plasma torch driven by a surface wave is presented. The theoretical model couples in a self-consistent way the wave electrodynamics and the electron and heavy particle kinetics. The set of coupled equations includes: Maxwell's equations, the electron Boltzmann equation, including electron-electron collisions, and the particle balance equations for electrons, excited atoms (4s, 4p, 3d, 5s, 5p, 4d, 6s), and atomic (Ar^+) and molecular ions (Ar2^+). The input parameters of the model are: gas pressure (760 Torr), plasma radius (R = 0.75 cm), dielectric permittivity (ɛd = 4.0) and tube thickness (d = 0.15 cm) as well as the measured axial profile of the gas temperature (3500 K - 1500 K). The latter was determined from measurements of the rotational temperature of the OH molecular band in the range 306 - 315 nm. Phase and amplitude sensitive recording provides the data for the axial wavenumber and wave attenuation coefficient. The wavenumber decreases along the generated plasma torch. The electron density (Ne) axial profile as determined from measurements of Hβ Stark broadening is in agreement with the theoretical one.

  1. Sterilization by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Adir Jose; Mansano, Ronaldo Domingues; Andreoli Pinto, Terezinha de Jesus; Ruas, Ronaldo; Silva Zambon, Luis da; Silva, Monica Valero da; Verdonck, Patrick Bernard

    2004-07-31

    The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy.

  2. Sterilization by oxygen plasma

    International Nuclear Information System (INIS)

    The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy

  3. Modeling electronegative plasma discharge

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenberg, A.J.; Lieberman, M.A. [Univ. of California, Berkley, CA (United States)

    1995-12-31

    Macroscopic analytic models for a three-component electronegative gas discharge are developed. Assuming the negative ions to be in Boltzmann equilibrium, a positive ion ambipolar diffusion equation is derived. The discharge consists of an electronegative core and electropositive edges. The electron density in the core is nearly uniform, allowing a parabolic approximation to the plasma profile to be employed. The resulting equilibrium equations are solved analytically and matched to a constant mobility transport model of an electropositive edge plasma. The solutions are compared to a simulation of a parallel-plane r.f. driven oxygen plasma for p = 50 mTorr and n{sub eo}= 2.4 x 10{sup 15} m{sup -3}. The ratio {alpha}{sub o} of central negative ion density to electron density, and the electron temperature T{sub e}, found in the simulation, are in reasonable agreement with the values calculated from the model. The model is extended to: (1) low pressures, where a variable mobility model is used in the electropositive edge region; and (2) high {alpha}{sub o} in which the edge region disappears. The inclusion of a second positive ion species, which can be very important in describing electronegative discharges used for materials processing, is a possible extension of the model.

  4. Plasma interaction with microbes

    International Nuclear Information System (INIS)

    The germicidal effects of a non-equilibrium atmospheric pressure plasma generated by a novel resistive barrier discharge on representatives of the two classes of bacteria (Gram-negative and Gram-positive) are discussed. The plasma exposure, while being lethal to both bacterial classes, also produced gross structural damage in the Gram-negative E. coli while none was observed in the more structurally robust Gram-positive Bacillus subtilis. An electrophysical process involving the role of the electrostatic tension on a charged body in a plasma is invoked to explain both observations. Since the efficacy of this electrophysical process depends not only on the tensile strength of the bacterial cell wall but also on its shape and texture, the need for more experimental studies, using a wide range of bacteria belonging to various morphological groups, is suggested. Ways to further test the validity of this electrophysical lysis mechanism for Gram-negative bacteria on one hand, and also to extend its operation to the more robust Gram-positive bacteria on the other, are suggested

  5. Innovative technical plasma applications

    International Nuclear Information System (INIS)

    Plasma is the predominant status of matter, in stars as well as in interstellar space. In science, it was only recognized rather late as a specific (fourth) state of matter: Sir William Crookes described it in 1879 as “radiant matter”, Irving Langmuir created the name “plasma” in 1928. Technically generated plasma is employed very broadly in modern technology. Some examples are Plasma Displays, Fluorescent Lamps (also the modern Energy Saving Lamps), Corona Discharges (for e.g. Ozone generation, or even engine ignition), arc welding and cutting, reactive ion etching, mass spectroscopy, ion rocket engines and many more. Very early since the development of the laser, it was also employed to generate a plasma (spark) in air or on surfaces. Generally, for this purpose at least ns (“Giant”) pulses have to be used. In more recent times, pico- and femtosecond pulses have allowed to create plasma very easily and effectively. Laser fusion may represent the ultimate application in this direction, based on highly amplified ns pulses for inertial confinement or ps pulses designed as fast igniter. The idea of employing laser pulses for the ignition of engines was attempted for the first time in 1978, although with inadequate tools like the CO2 laser. After a long time of inactivity in this field, about 10 years ago a few institutions like Vienna University of Technology first resumed this approach with the help of modern type solid-state lasers and started systematic investigations around the idea of laser ignition of internal combustion engines. Now, this technique has reached a high degree of maturity; remaining problems lie on the development level and are to be solved soon. Ambitious product development by leading engine producers or ignition equipment suppliers has been started world-wide since several years and, as a result, in one or two years laser ignition will probably be imple-mented into high power gas engines or, somewhat later, high-priced automotive

  6. Visualization of intermittent blobby plasma transport in attached and detached plasmas of the NAGDIS-II

    International Nuclear Information System (INIS)

    We investigated the intermittent convective plasma transport in a attached and/or detached plasma condition of the linear divertor plasma simulator, NAGDIS-II. Images taken by a fast-imaging camera clearly show that in attached plasmas, blobs are peeled off the bulk plasma, and propagate outward with an azimuthal motion. In detached plasmas, plasma turbulence observed near the plasma recombining region drives strong intermittent radial plasma transport, which could broaden the radial density profile. (author)

  7. Clinical use of Plasma and Plasma Fractions in Bleeding Disorders

    Institute of Scientific and Technical Information of China (English)

    王兆钺

    2008-01-01

    Internal and/or external bleeding is a common and sometimes very severe clinical manifestations of disorders of hemostasis. It may follow minor trauma or may arise apparently spontaneously. Disorders of hemostasis are generally divided into those caused by abnormalities of platelets, abnormalities of blood vessels, abnormalities of plasma coagulation factors, and hyperfibrinolysis, or com-binations of these. The use of plasma and plasma fractions dependents on the causing diseases and their severity. Several plasma products and plasma fractions are availa-ble in China and other plasma components and deriva-tives are commercially obtained. There have been the guidelines for their clinical use, and the revised ones will soon be published by Chinese Medical Association.

  8. Vaporized wall material/plasma interaction during plasma disruption

    International Nuclear Information System (INIS)

    The purpose of this paper is to discuss a new plasma disruption model that has been developed for analyzing the consequences to the limiter/first wall structures. This model accounts for: nonequilibrium surface vaporization for the ablating structure, nonequilibrium ionization of and radiation emitted from the ablated material in the plasma, plasma particle and energy transport, and plasma electromagnetic field evolution during the disruption event. Calculations were performed for a 5 ms disruption on a stainless steel flat limiter as part of a d-shaped first wall. These results indicated that the effectiveness of the ablated wall material to shield the exposed structure is greater than predicted by earlier models, and that the rate of redeposition of the ablated wall material ions is very dramatic. Impurity transport along magnetic field lines, global plasma motion, and radiation transport in an optically thick plasma are important factors that require additional modeling. Experimental measurements are needed to verifty these models

  9. Rydberg atoms in ultracold plasmas

    Science.gov (United States)

    Rolston, Steven

    2009-05-01

    Ultracold plasmas are formed through the photoionization of laser-cooled atoms, or spontaneous ionization of a dense cloud of Rydberg atoms or now molecules[1]. Ultracold plasmas are inherently metastable, as the ions and electrons would be in a lower energy state bound together as atoms. The dominant process of atom formation in these plasmas is three-body recombination, a collision between two electrons and an ion that leads to the formation of a Rydberg atom. This collisional process is not only important in determining the lifetime and density of the plasma, but is also critical in determining the time evolution of the temperature. The formation of the Rydberg atoms is accompanied by an increase in electron energy for the extra electron in the collision, and is a source of heating in these plasmas. Classical three-body recombination theory scales as T-9/2, and thus as a plasma cools due to a process such as adiabatic expansion, recombination-induced heating turns on, limiting the temperature [2]. The Rydberg atoms formed live in the plasma and contribute to the temperature dynamics, as collisions with plasma electrons can change the principal quantum number of the Rydberg atom, driving it to more tightly bound states (a source of plasma heating) or to higher states (a source of plasma cooling). If the plasma is cold and dense enough to be strongly coupled, classical three-body recombination theory breaks down. Recent theoretical work [3] suggests that the rate limits as the plasma gets strongly coupled. I will review the role of Rydberg atoms in ultracold plasmas and prospects for probing Rydberg collisions in the strongly coupled environment. [4pt] [1] J. P. Morrison, et al., Phys. Rev. Lett. 101, 205005 (2008 [0pt] [2] R. S. Fletcher, X. Zhang, and S. L. Rolston, Phys. Rev. Lett. 99, 145001 (2007 [0pt] [3] T. Pohl, private communication.

  10. The diverse applications of plasma

    Science.gov (United States)

    Sharma, Mukul; Dubey, Shivani; Darwhekar, Gajanan; Jain, Sudhir Kumar

    2015-07-01

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  11. The diverse applications of plasma

    International Nuclear Information System (INIS)

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences

  12. The diverse applications of plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Mukul, E-mail: mukulsharma@acropolis.edu.in; Darwhekar, Gajanan, E-mail: gdarwhekar@acropolis.edu.in [Acropolis Institute of Pharmaceutical Education & Research, Indore MP India (India); Dubey, Shivani, E-mail: dubeyshivani08@rediffmail.com [Mata Gujri College of Professional Studies, Indore MP India (India); Jain, Sudhir Kumar, E-mail: sudhirkjain1@rediffmail.com [School of Studies in Microbiology, Vikram University, Ujjain MP India (India)

    2015-07-31

    Plasma being the fourth state of matter has always been an attraction for Physicists and Chemists. With the advent of time, plasma energy has been recognized in having widening horizons in the field of Biomedical Sciences. Plasma medicine can be subdivided into three main fields; Non-thermal atmospheric-pressure direct plasma for medical therapy; Plasma-assisted modification of bio-relevant surfaces and Plasma-based bio-decontamination and sterilization. The basis of the research is that as it has free carrier molecules, it has the ability to target specific cells and regulate functions like wound healing. Plasma does not harm healthy human cells but can kill bacteria and possibly even cancer cells to help treat various diseases. Nosocomial infection control, prevention and containment of contagious diseases, disinfection of medical devices, surface treatment (heat and UV sensitive surfaces) are research of interest. Recent success in generating plasma at very low temperature ie. Cold plasma makes the therapy painless. It has the ability to activate cellular responses and important mechanisms in the body. They target specific molecules such as prothrombin for blood coagulation, cytokines for killing bacteria, and angiogenesis for tissue regeneration. Plasma has bactericidal, fungicidal and virucidal properties. Plasma technology has flourishing future in diverse fields like Textiles, Nanofabrication, Automotives, Waste management, Microbiology, Food Hygiene, Medical Science like Skin treatments, sterilisation of wounds, Hand disinfection, Dental treatments etc. Food hygiene using plasma can be achieved in disinfection of food containers, food surface disinfection, hygiene in food handling, preparation and packaging. Therefore Plasma is most promising field for budding Scientist for fluorishing research in Biological Sciences.

  13. The plasma-sheath transition in an asymmetric collisionless plasma

    International Nuclear Information System (INIS)

    The plasma sheath problem (λD → 0) for an asymmetric warm collision free plasma is solved in plane parallel geometry. To this end Emmert's model source term is generalized to account for a superimposed plasma drift. The quasineutral plasma approximation results in a system of coupled integral equations which can be solved analytically. In contrast to Emmert's symmetric model the upstream facing sheath edge shows the usual field singularity. At the downstream facing sheath edge we find a finite field strength and an oversatisfied Bohm criterion. These results are in full agreement with general considerations on the Bohm criterion and on the sheath edge field singularity. (orig.)

  14. Revisiting the plasma sheath—dust in plasma sheath

    Science.gov (United States)

    Das, G. C.; Deka, R.; Bora, M. P.

    2016-04-01

    In this work, we have considered the formation of warm plasma sheath in the vicinity of a wall in a plasma with considerable presence of dust particles. As an example, we have used the parameters relevant in case of plasma sheath formed around surfaces of various solid bodies in space, though the results obtained in this work can be applied to any other physical situation such as laboratory plasma. In the ion-acoustic time scale, we neglect the dust dynamics. The dust particles affect the sheath dynamics by affecting the Poisson equation which determines the plasma potential in the sheath region. It is important to note that our calculations are valid only when the amount of dust particles is not sufficient so as to affect the plasma dynamics in the dust-acoustic time scale, but enough to affect the plasma sheath. We have assumed the current to a dust particle to be balanced throughout the analysis. This makes the grain potential dependent on plasma potential, which is then incorporated into the Poisson equation. The resultant numerical model becomes an initial value problem, which is described by a 1-D integro-differential equation, which is then solved self-consistently by incorporating the change in plasma potential caused by inclusion of the dust potential in the Poisson equation.

  15. A contoured gap coaxial plasma gun with injected plasma armature

    Science.gov (United States)

    Witherspoon, F. Douglas; Case, Andrew; Messer, Sarah J.; Bomgardner, Richard; Phillips, Michael W.; Brockington, Samuel; Elton, Raymond

    2009-08-01

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  16. Laser beam-plasma coupling in laser solenoid plasmas

    International Nuclear Information System (INIS)

    A model has been constructed to analyze the gross beam-plasma interaction in a laser solenoid plasma. The model includes a simple solution for a slab plasma response to a given laser beam, and a solution for axial beam size variations in response to arbitrary axial plasma structure. The two solutions are combined to determine the coupled behavior. Trapping of the focused laser beam where it enters the plasma is a significant problem, but can be achieved by a minimum level of imbedded field in the plasma. If the beam is trapped, it first focuses and then defocuses near the front of the bleaching wave (front of the laser heated plasma). In order to avoid divergence of the beam near the front, it is essential to have a pre-formed favorable density profile in the plasma. Such a condition is probably achieved automatically in the early stages of plasma heating. Several techniques are discussed which can be used to avert unfavorable refractive behavior (catastrophic self-focusing and defocusing)

  17. A contoured gap coaxial plasma gun with injected plasma armature

    International Nuclear Information System (INIS)

    A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 μg of plasma with density above 1017 cm-3 to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 μg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

  18. Long Term Evolution of Plasma Wakefields

    OpenAIRE

    Sahai, Aakash A.; Katsouleas, T. C.; Tsung, F. S.; Mori, W. B.

    2014-01-01

    We study the long-term evolution (LTE) of plasma wakefields over multiple plasma-electron periods and few plasma-ion periods, much less than a recombination time. The evolution and relaxation of such a wakefield-perturbed plasma over these timescales has important implications for the upper limits of repetition-rates in plasma colliders. Intense fields in relativistic lasers (or intense beams) create plasma wakefields (modes around {\\omega}pe) by transferring energy to the plasma electrons. C...

  19. Plasma diagnostics discharge parameters and chemistry

    CERN Document Server

    Auciello, Orlando

    1989-01-01

    Plasma Diagnostics, Volume 1: Discharge Parameters and Chemistry covers seven chapters on the important diagnostic techniques for plasmas and details their use in particular applications. The book discusses optical diagnostic techniques for low pressure plasmas and plasma processing; plasma diagnostics for electrical discharge light sources; as well as Langmuir probes. The text also describes the mass spectroscopy of plasmas, microwave diagnostics, paramagnetic resonance diagnostics, and diagnostics in thermal plasma processing. Electrical engineers, nuclear engineers, microwave engineers, che

  20. The marker of cobalamin deficiency, plasma methylmalonic acid, correlates to plasma creatinine

    DEFF Research Database (Denmark)

    Hvas, A M; Juul, S; Gerdes, Lars Ulrik;

    2000-01-01

    : Records on 1689 patients who had their first plasma methylmalonic acid measurement during 1995 and 1996, and who had a simultaneous measurement of plasma cobalamins. Plasma creatinine values measured within a week of measurements of plasma methylmalonic acid and plasma cobalamins were available for 1255...... of the patients. MAIN OUTCOME MEASURES: Predictors of variation in plasma methylmalonic acid; plasma cobalamins, plasma creatinine, age and sex. RESULTS: Plasma methylmalonic acid was positively correlated with plasma creatinine, even for plasma creatinine within the normal range. These associations...... remained in a multiple regression analysis. For plasma cobalamins below 200 pmol L-1, there was a strong negative correlation between plasma methylmalonic acid and plasma cobalamins, whilst the association was weak for higher plasma cobalamin levels. Plasma methylmalonic acid increased and plasma...

  1. Whistler wave driven plasma thruster

    International Nuclear Information System (INIS)

    High density plasma can be generated by electron cyclotron resonance heating (ECRH) using whistler waves at densities for which the plasma frequency is much higher than the cyclotron frequency. This will result in a thruster operating at specific impulses of 103--104 s and much higher power and thrust densities than usual for ECRH devices. As the plasma generation is by electromagnetic waves, there are no electrodes, and wall material problems are greatly eased, permitting reliable, long lifetime operation. We report on the modeling of such a thruster, including plasma flow as well as losses to an end wall and ionization. A helical antenna to couple the waves into the plasma column is analyzed, including effects of the anisotropic plasma dielectric constant. An initial experiment to test the concept is planned

  2. The control of TCV plasmas

    International Nuclear Information System (INIS)

    The general control of tokamak plasmas has evolved considerably over the last few years with an increase in the plasma pulse length, an increase in the control of additional heating and fuelling and an increase in the degree to which the shape of the plasma can be varied. The TCV tokamak is specifically designed to explore the operational benefits of plasma shaping over a wide variety of plasma shapes. Consequently, considerable attention has been given to the control of the poloidal field coil currents which impose the desired shape. This paper deals with all aspects of the control of TCV plasmas, from the diagnostic measurements to the power supplies, via control algorithms and overall supervision. (author) 44 figs., tabs., 25 refs

  3. The control of TCV plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Lister, J.B.; Hofmann, F.; Moret, J.M. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)] [and others

    1996-07-01

    The general control of tokamak plasmas has evolved considerably over the last few years with an increase in the plasma pulse length, an increase in the control of additional heating and fuelling and an increase in the degree to which the shape of the plasma can be varied. The TCV tokamak is specifically designed to explore the operational benefits of plasma shaping over a wide variety of plasma shapes. Consequently, considerable attention has been given to the control of the poloidal field coil currents which impose the desired shape. This paper deals with all aspects of the control of TCV plasmas, from the diagnostic measurements to the power supplies, via control algorithms and overall supervision. (author) 44 figs., tabs., 25 refs.

  4. Three-dimensional magnetic perturbation fields in fusion plasmas: plasma edge transport and plasma surface interaction

    International Nuclear Information System (INIS)

    Three-dimensional (3D) magnetic perturbation fields are applied to high temperature plasma experiments to optimize the transport in the plasma edge and the resulting plasma wall interaction. While 3D magnetic field topologies are inherent to stellarator devices, the application of small, external 3D magnetic perturbation fields is a new and promising approach in tokamaks to control cyclic edge instabilities causing impulsive heat and particle loads to the first wall. The external 3D field applied breaks the axisymmetry and the standard assumptions for plasma edge transport are not valid anymore. Thus the resulting plasma surface interaction is governed by the 3D field structure. This talk will survey experimental results on the formation of such a 3D plasma boundary and the stationary plasma edge transport is studied with a Monte-Carlo fluid plasma and kinetic neutral transport model (EMC3-Eirene) in direct comparison to the experiment. It is shown that a 3D plasma boundary is induced resulting in 3D plasma surface particle and heat fluxes. Experimental quantification of the resulting material erosion at the wall elements shows that the net-erosion characteristic in a 3D boundary is highly dependent on the actual location in the 3D topology.

  5. Plasma Sources for Medical Applications - A Comparison of Spot Like Plasmas and Large Area Plasmas

    Science.gov (United States)

    Weltmann, Klaus-Dieter

    2015-09-01

    Plasma applications in life science are currently emerging worldwide. Whereas today's commercially available plasma surgical technologies such as argon plasma coagulation (APC) or ablation are mainly based on lethal plasma effects on living systems, the newly emerging therapeutic applications will be based on selective, at least partially non-lethal, possibly stimulating plasma effects on living cells and tissue. Promising results could be obtained by different research groups worldwide revealing a huge potential for the application of low temperature atmospheric pressure plasma in fields such as tissue engineering, healing of chronic wounds, treatment of skin diseases, tumor treatment based on specific induction of apoptotic processes, inhibition of biofilm formation and direct action on biofilms or treatment of dental diseases. The development of suitable and reliable plasma sources for the different therapies requires an in-depth knowledge of their physics, chemistry and parameters. Therefore much basic research still needs to be conducted to minimize risk and to provide a scientific fundament for new plasma-based medical therapies. It is essential to perform a comprehensive assessment of physical and biological experiments to clarify minimum standards for plasma sources for applications in life science and for comparison of different sources. One result is the DIN-SPEC 91315, which is now open for further improvements. This contribution intends to give an overview on the status of commercial cold plasma sources as well as cold plasma sources still under development for medical use. It will discuss needs, prospects and approaches for the characterization of plasmas from different points of view. Regarding the manageability in everyday medical life, atmospheric pressure plasma jets (APPJ) and dielectric barrier discharges (DBD) are of special interest. A comprehensive risk-benefit assessment including the state of the art of commercial sources for medical use

  6. Plasma beta HCG determination

    International Nuclear Information System (INIS)

    There are three important indications for the early diagnosis of pregnancy through the determination of the beta sub-unit of chorionic gonadotrophin using radioimmunoassay: 1) some patient's or doctor's anxiety to discover the problem; 2) when it will be necessary to employ diagnostic or treatment procedures susceptible to affect the ovum; and 3) in the differential diagnosis of amenorrhoea, uterine hemorrhage and abdominal tumors. Other user's are the diagnosis of missed absortion, and the diagnosis and follow-up of chrorioncarcinoma. The AA. studied 200 determinations of plasma beta-HCG, considering the main difficulties occuring in the clinical use of this relevant laboratory tool in actual Obstetrics. (author)

  7. Optical plasma diagnostics

    International Nuclear Information System (INIS)

    The measurement is described of the radial courses of temperature and electron, atom and ion density in the plasma of a water-stabilized arc with currents from 20 A to 60 A. For temperature measurement a method based on the determination of the relative intensity of Balmer lines was used. The electron density was measured by determining the Hsub(β) line profile and the relative density of other particles was measured by determining the intensity ratio of radiation emitted by the respective atoms or ions. (author)

  8. Inner magnetosphere plasma densities

    International Nuclear Information System (INIS)

    The radio plasma imager (RPI) on the IMAGE satellite performs radio sounding in the magnetosphere, transmitting coded signals stepping through the frequency range of interest and receiving the returned echoes. The measurements provide the echo amplitude as a function of frequency and echo delay time on a so-called plasmagram. A newly developed algorithm inverts THE echo traces on a plasmagram to electron density spatial distributions. Based on these observed density distributions, an empirical model is constructed to describe the two-dimensional density distribution in the inner magnetosphere. (author)

  9. Theoretical plasma physics

    International Nuclear Information System (INIS)

    During the past year we have studied stellarator equilibria with quasi-helical symmetry and the relation between the trajectories of the exact and the drift Hamiltonian. The relation between these trajectories is particularly important to issue of α particle confinement in a reactor. Work has also been done on the bootstrap current in the absence of symmetry, the effects of tearing modes on the current profile in a tokamak, and models of plasma turbulence. In addition, considerable time was spent during the year by Allen Boozer chairing the task force on Alternate Transport as part of the DoE transport initiative

  10. Bolometer for plasma diagnostics

    International Nuclear Information System (INIS)

    The construction of a low-inertia metallic bolometer with a bismuth thermistor, a time resolution 1.5-7 μsec, and a sensitivity 10-4-10-5J/cm2 is described which allows complete elimination of the internal photoeffect across the thermistor and avoidance of current contacts with the plasma. The presence of grids with retarding potentials allows separate recording of the energy contributions of charged particles, neutrals, and radiation in the absorption range of the receiving plate of the bolometer, as well as determination of the energy spectrum of the charged particles

  11. Plasma wake field accelerator

    International Nuclear Information System (INIS)

    A new scheme of electron acceleration, employing relativistic electron bunches in a cold plasma, is analyzed. The wake field of a leading bunch is derived in a single-particle model. We then extend the model to include finite bunch length effect. In particular, we discuss the relation between the charge distributions of the driving bunch and the energies transformable to the trailing electrons. It is shown that for symmetric charge distribution of the driving bunches, the maximum energy gain for a driven electron is 2γ0mc2. This limitation can be overcome by introducing asymmetric charge distributions. 13 refs., 5 figs

  12. Renormalization and plasma physics

    International Nuclear Information System (INIS)

    A review is given of modern theories of statistical dynamics as applied to problems in plasma physics. The derivation of consistent renormalized kinetic equations is discussed, first heuristically, later in terms of powerful functional techniques. The equations are illustrated with models of various degrees of idealization, including the exactly soluble stochastic oscillator, a prototype for several important applications. The direct-interaction approximation is described in detail. Applications discussed include test particle diffusion and the justification of quasilinear theory, convective cells, E vector x B vector turbulence, the renormalized dielectric function, phase space granulation, and stochastic magnetic fields

  13. Computational Methods in Plasma Physics

    CERN Document Server

    Jardin, Stephen

    2010-01-01

    Assuming no prior knowledge of plasma physics or numerical methods, Computational Methods in Plasma Physics covers the computational mathematics and techniques needed to simulate magnetically confined plasmas in modern magnetic fusion experiments and future magnetic fusion reactors. Largely self-contained, the text presents the basic concepts necessary for the numerical solution of partial differential equations. Along with discussing numerical stability and accuracy, the author explores many of the algorithms used today in enough depth so that readers can analyze their stability, efficiency,

  14. Plasma cell granuloma of lip

    Directory of Open Access Journals (Sweden)

    B Sabarinath

    2012-01-01

    Full Text Available Plasma cells are medium-sized round-to-oval cells with eccentrically placed nuclei, usually found in the red pulp of the spleen, tonsils, medulla of the lymph nodes, nasal mucosa, upper airway, lamina propria of the gastrointestinal tract, and sites of inflammation. Plasma cell granuloma is a rare reactive tumor-like proliferation composed chiefly of plasmacytic infiltrate. Here, we present a case of plasma cell granuloma of lip in a female patient.

  15. Monitoring system for thermal plasma

    International Nuclear Information System (INIS)

    In the Thermal plasma applications laboratory it has been the degradation project of oils for isolation in transformers. These are a very hazardous residues and at this time in the country they are stored in metal barrels. It has been the intention to undergo the oils to plasma for degradate them to non-hazardous residues. The system behavior must be monitored to establish the thermal plasma behavior. (Author)

  16. Important plasma problems in astrophysics

    International Nuclear Information System (INIS)

    In astrophysics, plasmas occur under very extreme conditions. For example there are ultra strong magnetic fields in neutron stars) relativistic plasmas around black holes and in jets, extremely energetic particles such as cosmic rays in the interstellar medium, extremely dense plasmas in accretion disks, and extremely large magnetic Reynold's numbers in the interstellar medium. These extreme limits for astrophysical plasmas make plasma phenomena much simpler to analyze in astrophysics than in the laboratory. An understanding of such phenomena often results in an interesting way, by simply taking the extreme limiting case of a known plasma theory. I will describe one of the more exciting examples. I will attempt to convey the excitement I felt when I was first exposed to it. However, not all plasma astrophysical phenomena are so simple. There are certain important plasma phenomena in astrophysics, which have not been so easily resolved. In fact a resolution of them is blocking significant progress in astrophysical research. They have not yet yielded to attacks by theoretical astrophysicists nor to extensive numerical simulation. I will attempt to describe one of the more important of these plasma-astrophysical problems, and discuss why its resolution is so important to astrophysics. This significant example is fast, magnetic reconnection. Another significant example is the large-magnetic-Reynold's-number MHD dynamos

  17. Technique for currentless plasma production

    International Nuclear Information System (INIS)

    The invention refers to high-frequency methods of plasma production and can be used in plasma facilities of the stellarator type as well as at the initial stage of discharge in tokamaks. To decrease energy expenditures, for plasma used production additional bleeding-in of neutral gas is performed in the solid pellets form by their injection to plasma confinement region. This excludes the necessity in pulse bleeding-in of a large gas volume and in rapid pumping-out of this gas

  18. Atomic phenomena in dense plasmas

    International Nuclear Information System (INIS)

    The following chapters are included: (1) the plasma environment, (2) perturbations of atomic structure, (3) perturbations of atomic collisions, (4) formation of spectral lines, and (5) dielectronic recombination

  19. Theory of Space Dusty Plasma

    Science.gov (United States)

    Mendis, A.

    2012-12-01

    Ionized gases, contaminated with fine (nanometer to micrometer-sized) charged dust, loosely referred to a dusty plasmas, occur in a wide variety of cosmic and laboratory environments. In this topical review I will discuss the underlying theory of such plasmas, with emphasis on the space environment. Central to the discussion is the electrostatic charging of the dust grains by the various currents that they experience in the plasma and radiative environment in which they are immersed. This charging could lead to both physical and dynamical consequences for the dust as well as for the plasma. Among the physical effects for the dust are electrostatic disruption and electrostatic levitation from charged surfaces. The dynamics of the charged dust is affected by the Lorentz force they experience, since space plasmas are generally magnetized. The physical effects for plasma result from the fact that the dust can act both as a sink and as a source of electrons in different space environments. The dynamical effects on the plasma arise from the fact that the charged dust can alter the phase velocity of normal wave modes (e.g., the Ion acoustic mode) by changing the charge equilibrium in the plasma. Additionally the charged dust can also participate in the wave dynamics, leading, for example, to the very low frequency, novel, "dust-acoustic" wave that has been observed in the laboratory. Finally the possibility that charged dust in a space plasma, may indirectly influence the propagation of electromagnetic radiation through it, will also be, briefly, discussed.

  20. Plasma on a foundry cupola

    Science.gov (United States)

    Pineau, Didier

    An experiment of a plasma torch on a production foundry cupola is reported. The test runs were conducted on a hot blast cupola, the blast temperature in the absence of plasma being 400 C. With the torch, the temperature of the blast was increased to 1000 C. The experiment was conducted for the manufacture of car engines with a 2.5 MW transportable plasma system. The cupola was boosted with a 4 MW torch and results included an increase in production of 45 percent, a decrease in coke rate and no more new iron in the loads. The plasma torch and hot air cupola furnace are described.

  1. Ultrarelativistic Electron-Positron Plasma

    CERN Document Server

    Thoma, Markus H

    2008-01-01

    Ultrarelativistic electron-positron plasmas can be produced in high-intensity laser fields and play a role in various astrophysical situations. Their properties can be calculated using QED at finite temperature. Here we will use perturbative QED at finite temperature for calculating various important properties, such as the equation of state, dispersion relations of collective plasma modes of photons and electrons, Debye screening, damping rates, mean free paths, collision times, transport coefficients, and particle production rates, of ultrarelativistic electron-positron plasmas. In particular, we will focus on electron-positron plasmas produced with ultra-strong lasers.

  2. Variation of plasma parameters in a modified mode of plasma production in a double plasma device

    Indian Academy of Sciences (India)

    A Phukan; M K Mishra; B K Saikia; M Chakraborty

    2010-03-01

    A modified mode of plasma production in a double plasma device is presented and plasma parameters are controlled in this configuration. Here plasma is produced by applying a discharge voltage between the hot filaments in the source (cathode) and the target magnetic cage (anode) of the device. In this configuration, the hot electron emitting filaments are present only in the source and the magnetic cage of this is kept at a negative bias such that due to the repulsion of the cage bias, the primary electrons can go to the grounded target and produce plasma there. The plasma parameters can be controlled by varying the voltages applied to the source magnetic cage and the separation grid of the device.

  3. Plasma-driven liners

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, H.; Linhart, J.G.; Bortolotti, A. [Ferrara Univ. (Italy). Dipt. di Fisica; Bilbao, L. [Buenos Aires Univ. (Argentina); Nardi, V. [Stevens Inst. of Tech., Hoboken, NJ (United States)

    1992-12-31

    The deposition of thermal energy by laser or ion beams in an ablator is capable of producing a very large acceleration of the adjacent pusher - for power densities of 100 Terrawatts/cm{sup 2}, ablator pressure in the range of 10 Mbar is attainable. In the case of a plasma drive such driving pressures and accelerations are not directly possible. When a snowplough (SP) is used to accelerate a thin liner, the driving pressure is that of the magnetic piston pushing the SP, i.e. at most 0.1 Mbar. However, the initial radius r{sub 0} of the liner can be a few centimeters, instead of 1 (mm) as in the case in direct pellet implosions. In order to compete with the performance of the beam-driven liners, the plasma drive must demonstrate that (a) thin liner retains a high density during the implosion (lasting a fraction of a {mu}sec); (b) radial compression ratio r{sub 0}/r{sub min} of the order of 100 can be attained. It is also attractive to consider the staging of two or more liners in order to get sharpening and amplifications of the pressure and/or radiation pulse. If (a) and (b) are verified then the final pressures produced will be comparable with those of the beam-driven implosions. (author) 5 refs., 3 figs.

  4. Plasma-driven liners

    International Nuclear Information System (INIS)

    The deposition of thermal energy by laser or ion beams in an ablator is capable of producing a very large acceleration of the adjacent pusher - for power densities of 100 Terrawatts/cm2, ablator pressure in the range of 10 Mbar is attainable. In the case of a plasma drive such driving pressures and accelerations are not directly possible. When a snowplough (SP) is used to accelerate a thin liner, the driving pressure is that of the magnetic piston pushing the SP, i.e. at most 0.1 Mbar. However, the initial radius r0 of the liner can be a few centimeters, instead of 1 (mm) as in the case in direct pellet implosions. In order to compete with the performance of the beam-driven liners, the plasma drive must demonstrate that a) thin liner retains a high density during the implosion (lasting a fraction of a μsec); b) radial compression ratio r0/rmin of the order of 100 can be attained. It is also attractive to consider the staging of two or more liners in order to get sharpening and amplifications of the pressure and/or radiation pulse. If a) and b) are verified then the final pressures produced will be comparable with those of the beam-driven implosions. (author) 5 refs., 3 figs

  5. Plasma YKL-40

    DEFF Research Database (Denmark)

    Jensen, Peter; Wiell, C; Milting, K;

    2013-01-01

    Background  Plasma YKL-40 is an inflammatory biomarker. No useful biomarker exists in patients with psoriasis or psoriatic arthritis. Objective  To measure YKL-40 and high-sensitivity C-reactive protein (hs-CRP) in patients with psoriasis or psoriatic arthritis before and during treatment. Methods......-CRP at inclusion and during 48 weeks of adalimumab treatment. The patients with psoriatic arthritis were divided into responders and non-responders. Results  In patients with psoriasis, the baseline median PASI score was 10.8 and baseline YKL-40 was 45 μg/L. Seventeen per cent had elevated plasma YKL-40...... responded to adalimumab (from 112 μg/L to 68 at 48 weeks, P = 0.007). Hs-CRP decreased (from 4.65 mg/L to 0.91, P = 0.013) in the responders. In the non-responders (n = 9), YKL-40 and hs-CRP remained unchanged. Conclusions  YKL-40 is elevated in many patients with psoriatic arthritis, but not in patients...

  6. Quark gluon plasma

    CERN Document Server

    Nayak, Tapan; Sarkar, Sourav

    2014-01-01

    At extremely high temperatures and densities, protons and neutrons may dissolve into a "soup" of quarks and gluons, called the Quark-Gluon Plasma (QGP). For a few microseconds, shortly after the Big Bang, the Universe was filled with the QGP matter. The search and study of Quark-Gluon Plasma (QGP) is one of the most fundamental research topics of our times. The QGP matter has been probed by colliding heavy ions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, New York and the Large Hadron Collider at CERN, Geneva. By colliding heavy-ions at a speed close to that of light, scientists aim to obtain - albeit over a tiny volume of the size of a nucleus and for an infinitesimally short instant - a QGP state. This QGP state can be observed by dedicated experiments, as it reverts to hadronic matter through expansion and cooling. This volume presents some of the current theoretical and experimental understandings in the field of QGP.

  7. Proton radiography in plasma

    Energy Technology Data Exchange (ETDEWEB)

    Volpe, L., E-mail: luca.volpe@mib.infn.it [Universita degli Studi di Milano-Bicocca, Piazza della scienza 3, Milano 20126 (Italy); Batani, D.; Morace, A. [Universita degli Studi di Milano-Bicocca, Piazza della scienza 3, Milano 20126 (Italy); Nicolai, Ph.; Regan, C. [CELIA, Universite de Bordeaux, CNRS, CEA, F33405 (France); Ravasio, A. [LULI, UMR 7605, CNRS, CEA, Universite Paris VI, Ecole Polytechnique, 91128 Palaiseau Cedex (France)

    2011-10-11

    Generation of high intensity and well collimated multi-energetic proton beams from laser-matter interaction extends the possibility to use protons as a diagnostic tool to image imploding target in Inertial Confinement Fusion (ICF) experiments. Due to the very large mass densities reached during implosion, protons traveling through the target undergo a very large number of collisions. Therefore the analysis of experimentally obtained proton images requires care and accurate numerical simulations using both hydrodynamic and Monte Carlo codes. The impact of multiple scattering needs to be carefully considered by taking into account the exact stopping power for dense matter and for the underdense plasma corona. In our paper, density, temperature and ionization degree profiles of the imploding target are obtained by 2D hydrodynamic simulations performed using CHIC code. Proton radiography images are simulated using the Monte Carlo code (MCNPX; adapted to correctly describe multiple scattering and plasma stopping power) in order to reconstruct the complete hydrodynamic history of the imploding target. Finally we develop a simple analytical model to study the performance of proton radiography as a function of initial experimental parameters, and identify two different regimes for proton radiography in ICF.

  8. The FORMEX plasma formulary

    International Nuclear Information System (INIS)

    A collection of formulas frequently used in the field of plasma physics has been compiled and prepared for evaluation with the Microsoft Excel spreadsheet program, which runs on an IBM-compatible PC as well as on a Macintosh computer. The present version of this plasma formulary, a worksheet named FORMEX, comprises 133 formulas depending on 23 variables. The formulas are evaluated numerically and these numerical values are promptly updated whenever any of the input variables is changed. A complete set of input variables can be chosen by the name of an experimental device. Stellarators and tokamaks, 16 altogether, have been incorporated in the formulary. A diagram can be displayed to show how a specific formula depends on any of its input variables. Each formula is extensively annotated to show it origin and give literature references. The formulary is operated with a series of macros, all inside the macro sheet named FORMAK, which are invoked by menu commands from a special menu bar. All the information from the formulary, the genuine formulas, the table of numerically evaluated plot coordinates, the notes, and the diagrams can be further processed or transferred to any other application with the help of the usual Excel commands. The formulary is open to adding more formulas and, if needed, variables as well as data of further experimental devices. The FORMEX and FORMAK files are made available by ANONYMOUS FTP via the address FTP.IPP-GARCHING.MPG.DE, which allows public access. (orig.)

  9. Plasma neutralization models for intense ion beam transport in plasma

    International Nuclear Information System (INIS)

    Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed based on the assumption of long charge bunches (lb >> rb). Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The analytical predictions for the degree of ion beam charge and current neutralization also agree well with the results of the numerical simulations. The model predicts very good charge neutralization (>99%) during quasi-steady-state propagation, provided the beam pulse duration τb is much longer than the electron plasma period 2π/ωp, where ωp = (4πe2np/m)1/2 is the electron plasma frequency, and np is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. The analytical formulas derived in this paper can provide an important benchmark for numerical codes, and provide scaling relations for different beam and plasma parameters

  10. Kinetic theory of plasma waves: Part II homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2000-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  11. KINETIC THEORY OF PLASMA WAVES: Part II: Homogeneous Plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2010-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves are discussed in the limit of the cold

  12. Kinetic theory of plasma waves - Part II: Homogeneous plasma

    NARCIS (Netherlands)

    Westerhof, E.

    2008-01-01

    The theory of electromagnetic waves in a homogeneous plasma is reviewed. The linear response of the plasma to the waves is obtained in the form of the dielectric tensor. Waves ranging from the low frequency Alfven to the high frequency electron cyclotron waves axe discussed in the limit of the cold

  13. Experimental results from detached plasmas in TFTR

    International Nuclear Information System (INIS)

    Detached plasmas are formed in TFTR which have the principal property of the boundary to the high temperature plasma core being defined by a radiating layer. This paper documents the properties of TFTR ohmic-detached plasmas with a range of plasma densities at two different plasma currents

  14. The effects of the rotation in plasma

    OpenAIRE

    Arteha, S. N.

    2000-01-01

    Electric and magnetic self-fields can exist in the rotating plasma. A self-sustained rotation can be established in the plasma. The disturbed distribution function of rotating plasma is derived from the Vlasov equation. The propagation of waves in rotating plasma differs from that in the usual plasma. New terms for Landau damping appear. The local rotational behaviour may become prevailing.

  15. Theoretical Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Vahala, George M. [College of William and Mary, Williamsburg, VA (United States)

    2013-12-31

    Lattice Boltzmann algorithms are a mesoscopic method to solve problems in nonlinear physics which are highly parallelized – unlike the direction solution of the original problem. These methods are applied to both fluid and magnetohydrodynamic turbulence. By introducing entropic constraints one can enforce the positive definiteness of the distribution functions and so be able to simulate fluids at high Reynolds numbers without numerical instabilities. By introducing a vector distribution function for the magnetic field one can enforce the divergence free condition on the magnetic field automatically, without the need of divergence cleaning as needed in most direct numerical solutions of the resistive magnetohydrodynamic equations. The principal reason for the high parallelization of lattice Boltzmann codes is that they consist of a kinetic collisional relaxation step (which is purely local) followed by a simple shift of the relaxed data to neighboring lattice sites. In large eddy simulations, the closure schemes are highly nonlocal – the most famous of these schemes is that due to Smagorinsky. Under a lattice Boltzmann representation the Smagorinsky closure is purely local – being simply a particular moment on the perturbed distribution fucntions. After nonlocal fluid moment models were discovered to represent Landau damping, it was found possible to model these fluid models using an appropriate lattice Boltzmann algorithm. The close to ideal parallelization of the lattice Boltzmann codes permitted us to be Gordon Bell finalists on using the Earth Simulation in Japan. We have also been involved in the radio frequency propagation of waves into a tokamak and into a spherical overdense tokamak plasma. Initially we investigated the use of a quasi-optical grill for the launching of lower hybrid waves into a tokamak. It was found that the conducting walls do not prevent the rods from being properly irradiated, the overloading of the quasi-optical grill is not severe

  16. Measurements of plasma potential in high-pressure microwave plasmas

    International Nuclear Information System (INIS)

    Plasma potential of a high-pressure (∼1 Torr) microwave-generated argon plasma is measured using a Langmuir probe and a cold emissive probe. The operation of a hot emissive probe in a high-pressure plasma has been very difficult due to frequent burn-outs and significantly reduced lifetime of the probe filament, which, in turn, limits the possibility of collecting a wide range of data. The I-V characteristics from both Langmuir and emissive probes are interpreted using the collisionless probe theory since the collision correction factor is not very significant. The plasma potential determined from both Langmuir and cold emissive probe characteristics agrees well with one another and is observed to be dependent on the operating gas pressure but relatively unchanged as a function of the microwave power. An average plasma potential determined over the operating range of microwave powers varies nonlinearly with the gas pressure.

  17. Nonlinear plasma and beam physics in plasma wake-fields

    International Nuclear Information System (INIS)

    In experimental studies of the Plasma Wake-field Accelerator performed to date at the Argonne Advanced Accelerator Test Facility, significant nonlinearities in both plasma and beam behavior have been observed. The plasma waves driven in the wake of the intense driving beam in these experiments exhibit three-dimensional nonlinear behavior which has as yet no quantitative theoretical explanation. This nonlinearity is due in part to the self-pinching of the driving beam in the plasma, as the denser self-focused beam can excite larger amplitude plasma waves. The self-pinching is a process with interesting nonlinear aspects: the initial evolution of the beam envelope and the subsequent approach to Bennett equilibrium through phase mixing. 35 refs., 10 figs

  18. Analysis of the incident plasma and vapor shield plasma in PLADIS I, a plasma disruption simulator

    International Nuclear Information System (INIS)

    Measurements have been made of the incident plasma and the vapor shielding plasma in the UNM plasma disruption simulator (PLADIS I). PLADIS I is a coaxial plasma gun that is used to investigate first wall interactions during tokamak disruptions. An optically thick vapor shield plasma has been observed to form above the target surface in PLADIS I and other disruption simulators, such as the VIKA experiment in St. Petersburg, Russia. Fast, two-color optical pyrometry is used to determine the energy density deposited during initial plasma/surface interaction, before the vapor shield becomes optically thick. Profiles of total energy density deposited in the target surface are measured using an array of calorimeters in a collaborative experiment with the Japan Atomic Energy Research Institute (JAERI). Data regarding the energy density profile of the incident plasma and the profile of energy density deposited in the target surface will be presented. Vacuum ultraviolet spectroscopy is used to determine the ionic composition of the optically thick vapor shield plasma in the PLADIS I and VIKA experiments. Analysis of these spectra have been complicated by the presence of impurities in the plasma. Data regarding these impurities will be presented. A time resolved target surface pressure diagnostic is in the final stages of assembly. Data regarding target surface pressure in PLADIS I as a function of incident power and energy will be presented

  19. Characteristics of plasma sterilizer using microwave torch plasma with AC high-voltage discharge plasma

    Science.gov (United States)

    Itarashiki, Tomomasa; Hayashi, Nobuya; Yonesu, Akira

    2016-01-01

    Microwave plasma sterilization has recently been attracting attention for medical applications. However, it is difficult to perform low-temperature sterilization in short time periods. Increasing the output power shortens the time required for sterilization but causes the temperature to increase. To overcome this issue, we have developed a hybrid plasma system that combines a microwave torch plasma and a high-voltage mesh plasma, which allows radicals to be produced at low temperatures. Using this system, successful sterilization was shown to be possible in a period of 45 min at a temperature of 41 °C.

  20. High-beta plasma blobs in the morningside plasma sheet

    Directory of Open Access Journals (Sweden)

    G. Haerendel

    Full Text Available Equator-S frequently encountered, i.e. on 30% of the orbits between 1 March and 17 April 1998, strong variations of the magnetic field strength of typically 5–15-min duration outside about 9RE during the late-night/early-morning hours. Very high-plasma beta values were found, varying between 1 and 10 or more. Close conjunctions between Equator-S and Geotail revealed the spatial structure of these "plasma blobs" and their lifetime. They are typically 5–10° wide in longitude and have an antisymmetric plasma or magnetic pressure distribution with respect to the equator, while being altogether low-latitude phenomena 
    (≤ 15°. They drift slowly sunward, exchange plasma across the equator and have a lifetime of at least 15–30 min. While their spatial structure may be due to some sort of mirror instability, little is known about the origin of the high-beta plasma. It is speculated that the morningside boundary layer somewhat further tailward may be the source of this plasma. This would be consistent with the preference of the plasma blobs to occur during quiet conditions, although they are also found during substorm periods. The relation to auroral phenomena in the morningside oval is uncertain. The energy deposition may be mostly too weak to generate a visible signature. However, patchy aurora remains a candidate for more disturbed periods.

    Key words. Magnetospheric physics (plasma convection; plasma sheet; plasma waves and instabilities

  1. Waves in plasmas (part 1 - wave-plasma interaction general background)

    International Nuclear Information System (INIS)

    This document gathers a series of transparencies presented in the framework of the week-long lectures 'hot plasmas 2004' and dedicated to the physics of wave-plasma interaction. The structure of this document is as follows: 1) wave and diverse plasmas, 2) basic equations (Maxwell equations), 3) waves in a fluid plasma, and 4) waves in a kinetic plasma (collisionless plasma)

  2. MHD control in burning plasmas MHD control in burning plasmas

    Science.gov (United States)

    Donné, Tony; Liang, Yunfeng

    2012-07-01

    Fusion physics focuses on the complex behaviour of hot plasmas confined by magnetic fields with the ultimate aim to develop a fusion power plant. In the future generation of tokamaks like ITER, the power generated by the fusion reactions substantially exceeds the external input power (Pfusion}/Pin >= 10). When this occurs one speaks of a burning plasma. Twenty per cent of the generated fusion power in a burning plasma is carried by the charged alpha particles, which transfer their energy to the ambient plasma in collisions, a process called thermalization. A new phenomenon in burning plasmas is that the alpha particles, which form a minority but carry a large fraction of the plasma kinetic energy, can collectively drive certain types of magneto-hydrodynamic (MHD) modes, while they can suppress other MHD modes. Both types of MHD modes can have desirable effects on the plasma, as well as be detrimental to the plasma. For example, the so-called sawtooth instability, on the one hand, is largely responsible for the transport of the thermalized alpha particles out of the core, but, on the other hand, may result in the loss of the energetic alphas before they have fully thermalized. A further undesirable effect of the sawtooth instability is that it may trigger other MHD modes such as neoclassical tearing modes (NTMs). These NTMs, in turn, are detrimental to the plasma confinement and in some cases may even lead to disruptive termination of the plasma. At the edge of the plasma, finally, so-called edge localized modes or ELMs occur, which result in extremely high transient heat and particle loads on the plasma-facing components of a reactor. In order to balance the desired and detrimental effects of these modes, active feedback control is required. An additional complication occurs in a burning plasma as the external heating power, which is nowadays generally used for plasma control, is small compared to the heating power of the alpha particles. The scientific challenge

  3. Supersonic induction plasma jet modeling

    Energy Technology Data Exchange (ETDEWEB)

    Selezneva, S.E. E-mail: svetlana2@hermes.usherbS_Selezneva2@hermes.usherb; Boulos, M.I

    2001-06-01

    Numerical simulations have been applied to study the argon plasma flow downstream of the induction plasma torch. It is shown that by means of the convergent-divergent nozzle adjustment and chamber pressure reduction, a supersonic plasma jet can be obtained. We investigate the supersonic and a more traditional subsonic plasma jets impinging onto a normal substrate. Comparing to the subsonic jet, the supersonic one is narrower and much faster. Near-substrate velocity and temperature boundary layers are thinner, so the heat flux near the stagnation point is higher in the supersonic jet. The supersonic plasma jet is characterized by the electron overpopulation and the domination of the recombination over the dissociation, resulting into the heating of the electron gas. Because of these processes, the supersonic induction plasma permits to separate spatially different functions (dissociation and ionization, transport and deposition) and to optimize each of them. The considered configuration can be advantageous in some industrial applications, such as plasma-assisted chemical vapor deposition of diamond and polymer-like films and in plasma spraying of nanoscaled powders.

  4. Model for resonant plasma probe.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Johnson, William Arthur; Hebner, Gregory Albert; Jorgenson, Roy E.; Coats, Rebecca Sue

    2007-04-01

    This report constructs simple circuit models for a hairpin shaped resonant plasma probe. Effects of the plasma sheath region surrounding the wires making up the probe are determined. Electromagnetic simulations of the probe are compared to the circuit model results. The perturbing effects of the disc cavity in which the probe operates are also found.

  5. Thermally stimulated scattering in plasmas

    DEFF Research Database (Denmark)

    Dysthe, K. B.; Mjølhus, E.; Pécseli, H. L.;

    1985-01-01

    A theory for stimulated scattering of a laser beam is formulated where the dominant nonlinearity is the ohmic heating of the plasma. The analysis is carried out with particular reference to experimental investigations of CO2 laser heating of linear discharge plasma. In the conditions characterizing...

  6. Plasma technology for waste treatment

    International Nuclear Information System (INIS)

    Improved environmental cleanup technology is needed to meet demanding goals for remediation and treatment of future waste streams. Plasma technology has unique features which could provide advantages of reduced secondary waste, lower cost, and onsite treatment for a wide variety of applications. Plasma technology can provide highly controllable processing without the need for combustion heating. It can be used to provide high temperature processing (∼10,000 degrees C). Plasma technology can also be employed for low temperature processing (down to room temperature range) through selective plasma chemistry. A graphite electrode arc plasma furnace at MIT has been used to investigate high temperature processing of simulated solid waste for Department of Energy environmental cleanup applications. Stable, non-leachable glass has been produced. To ensure reliable operation and to meet environmental objectives, new process diagnostics have been developed to measure furnace temperature and to determine metals emissions in the gaseous effluent. Selective plasma destruction of dilute concentrations of hazardous compounds in gaseous waste streams has been investigated using electron beam generated plasmas. Selective destruction makes it possible to treat the gas steam at relatively low temperatures in the 30-300 degrees C range. On-line infrared measurements have been used in feedback operation to maximize efficiency and ensure desired performance. Plasma technology and associated process diagnostics will be used in future studies of a wide range of waste streams

  7. N-body plasma simulation

    International Nuclear Information System (INIS)

    The N-Body plasma simulation consists in calculating the Coulomb interaction between N charged particles. We adapted an N-Body 'tree code' algorithm, successfully used in the gravitational case, for the simulation of plasma. So far, we have found two main applications which suits this technique particularly well. First, the expansion of a plasma into vacuum. In this kind of simulations, densities of very different order of magnitude have to interact. Some areas can have an hydrodynamic behavior whereas some others are filled by energetic particles following ballistic trajectories. Problems which take into account plasma-vacuum interface are almost impossible to study with common simulation techniques ( Vlasov, Fokker-Planck). The other application consists in simulating moderately or strongly coupled plasma. It deals with many laboratory plasmas as well as astrophysical plasmas such as the convective zone of the sun. In coupled plasmas, close collisions between charges can not be neglected as it is done in most of the other simulation techniques. The N-Body technique allows the accurate description of the trajectory of each single particle and thus to take into account the strong deviations due to the close collisions. (author)

  8. Waves and instabilities in plasmas

    CERN Document Server

    Chen Liu

    1987-01-01

    The topics covered in these notes are selective and tend to emphasize more on kinetic-theory approaches to waves and instabilities in both uniform and non-uniform plasmas, students are assumed to have some basic knowledge of plasma dynamics in terms of single-particle and fluid descriptions.

  9. Fundamental studies of fusion plasmas

    International Nuclear Information System (INIS)

    In this paper, summary reports are given on significant new results for understanding and controlling tokamak performance under the application of high power ICH; new results on understanding the complicated interaction of plasma, atomic and surface physics in the tokamak edge plasma with intense rf fields; and new results on the neoclassical transport of energetic alpha particles

  10. Turbulent transport in magnetized plasmas

    CERN Document Server

    Horton, Wendell

    2012-01-01

    This book explains how magnetized plasmas self-organize in states of electromagnetic turbulence that transports particles and energy out of the core plasma faster than anticipated by the fusion scientists designing magnetic confinement systems in the 20th century. It describes theory, experiments and simulations in a unified and up-to-date presentation of the issues of achieving nuclear fusion power.

  11. Solitons and chaos in plasma

    International Nuclear Information System (INIS)

    Plasma exhibits a full of variety of nonlinear phenomena. Active research in nonlinear plasma physics contributed to explore the concepts of soliton and chaos. Structure of soliton equations and dynamics of low dimensional Hamiltonian systems are discussed to emphasize the universality of these novel concepts in the wide branch of science and engineering. (author) 52 refs

  12. Plasma chemistry and organic synthesis

    Science.gov (United States)

    Tezuka, M.

    1980-01-01

    The characteristic features of chemical reactions using low temperature plasmas are described and differentiated from those seen in other reaction systems. A number of examples of applications of plasma chemistry to synthetic reactions are mentioned. The production of amino acids by discharge reactions in hydrocarbon-ammonia-water systems is discussed, and its implications for the origins of life are mentioned.

  13. Fully relativistic plasma dispersion function

    Science.gov (United States)

    Kamp, Léon P. J.

    1994-12-01

    Properties of a relativistic plasma dispersion function (PDF) that is required for the description of waves propagating perpendicular to a magnetic field in a fully relativistic, magnetized, Maxwellian plasma, are presented. Series, asymptotic series, recurrence relations, integral representations, derivatives, generating functions, approximations, differential equations, and connections with standard transcendental functions are discussed, as are the PDF's analytic properties.

  14. Polarization spectroscopy of tokamak plasmas

    International Nuclear Information System (INIS)

    Measurements of polarization of spectral lines emitted by tokamak plasmas provide information about the plasma internal magnetic field and the current density profile. The methods of polarization spectroscopy, as applied to the tokamak diagnostic, are reviewed with emphasis on the polarimetry of motional Stark effect in hydrogenic neutral beam emissions. 25 refs., 7 figs

  15. Laser-aided plasma diagnostics

    NARCIS (Netherlands)

    Donne, A. J. H.; Barth, C. J.; Weisen, H.

    2008-01-01

    Laser-aided diagnostics are widely applied in the field of high-temperature plasma diagnostics for a large variety of measurements. Incoherent Thomson scattering is used for highly localized measurements of the electron temperature and density in the plasma. Coherent Thomson scattering yields inform

  16. Conductivity of a Relativistic Plasma

    CERN Document Server

    Braams, B J; Braams, Bastiaan J.; Karney, Charles F. F.

    1989-01-01

    The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. In this formulation the collision operator is expressed in terms of five scalar potentials which are given by one-dimensional integrals over the distribution function. This formulation is used to calculate the electrical conductivity of a uniform electron-ion plasma with infinitely massive ions.

  17. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.;

    1968-01-01

    The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3......The B field configuration of a Q-device has been modified into a magnetic Laval nozzle. Continuous supersonic plasma flow is observed with M≈3...

  18. Continuous supersonic plasma wind tunnel

    DEFF Research Database (Denmark)

    Andersen, S.A.; Jensen, Vagn Orla; Nielsen, P.;

    1969-01-01

    The normal magnetic field configuration of a Q device has been modified to obtain a 'magnetic Laval nozzle'. Continuous supersonic plasma 'winds' are obtained with Mach numbers ~3. The magnetic nozzle appears well suited for the study of the interaction of supersonic plasma 'winds' with either...

  19. Biocompatibility of plasma nanostructured biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Slepičková Kasálková, N. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Slepička, P., E-mail: petr.slepicka@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Bačáková, L. [Institute of Physiology, Academy of Sciences of the Czech Republic 142 20 Prague (Czech Republic); Sajdl, P. [Department of Power Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Švorčík, V. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic)

    2013-07-15

    Many areas of medicine such as tissue engineering requires not only mastery of modification techniques but also thorough knowledge of the interaction of cells with solid state substrates. Plasma treatment can be used to effective modification, nanostructuring and therefore can significantly change properties of materials. In this work the biocompatibility of the plasma nanostructured biopolymers substrates was studied. Changes in surface chemical structure were studied by X-ray photoelectron spectroscopy (XPS). The morphology pristine and modified samples were determined using atomic force microscopy (AFM). The surface wettability was determined by goniometry from contact angle. Biocompatibility was determined by in vitro tests, the rat vascular smooth muscle cells (VSMCs) were cultivated on the pristine and plasma modified biopolymer substrates. Their adhesion, proliferation, spreading and homogeneous distribution on polymers was monitored. It was found that the plasma treatment leads to rapid decrease of contact angle for all samples. Contact angle decreased with increasing time of modification. XPS measurements showed that plasma treatment leads to changes in ratio of polar and non-polar groups. Plasma modification was accompanied by a change of surface morphology. Biological tests found that plasma treatment have positive effect on cells adhesion and proliferation cells and affects the size of cell’s adhesion area. Changes in plasma power or in exposure time influences the number of adhered and proliferated cells and their distribution on biopolymer surface.

  20. Experimental Plasma Research. Project summaries

    International Nuclear Information System (INIS)

    This is the fifth in a series of Project Summary books going back to 1976. They are issued approximately every two years and provide a short description of each project supported by the Experimental Plasma Research Branch of the Division of Applied Plasma Physics in the Office of Fusion Energy

  1. Edge plasma diagnostics in tokamaks

    Czech Academy of Sciences Publication Activity Database

    Stöckel, Jan; Brotánková, Jana; Hron, Martin; Adámek, Jiří; Ďuran, Ivan; Van Oost, G.; Peleman, P.; Gunn, J.; Devynck, P.; Martines, E.; Schrittwieser, R.; Kocan, M.

    Kudowa Zdrój : -, 2006, s. 910-935. [Sixth International Workshop and Summer School Towards Fusion Energy - Plasma Physics, Diagnostics, Spin-offs. Kudowa Zdrój (PL), 18.09.2006-22.09.2006] Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * diagnostics * heating Subject RIV: BL - Plasma and Gas Discharge Physics

  2. Biocompatibility of plasma nanostructured biopolymers

    International Nuclear Information System (INIS)

    Many areas of medicine such as tissue engineering requires not only mastery of modification techniques but also thorough knowledge of the interaction of cells with solid state substrates. Plasma treatment can be used to effective modification, nanostructuring and therefore can significantly change properties of materials. In this work the biocompatibility of the plasma nanostructured biopolymers substrates was studied. Changes in surface chemical structure were studied by X-ray photoelectron spectroscopy (XPS). The morphology pristine and modified samples were determined using atomic force microscopy (AFM). The surface wettability was determined by goniometry from contact angle. Biocompatibility was determined by in vitro tests, the rat vascular smooth muscle cells (VSMCs) were cultivated on the pristine and plasma modified biopolymer substrates. Their adhesion, proliferation, spreading and homogeneous distribution on polymers was monitored. It was found that the plasma treatment leads to rapid decrease of contact angle for all samples. Contact angle decreased with increasing time of modification. XPS measurements showed that plasma treatment leads to changes in ratio of polar and non-polar groups. Plasma modification was accompanied by a change of surface morphology. Biological tests found that plasma treatment have positive effect on cells adhesion and proliferation cells and affects the size of cell’s adhesion area. Changes in plasma power or in exposure time influences the number of adhered and proliferated cells and their distribution on biopolymer surface

  3. Plasma Processes for Semiconductor Fabrication

    Science.gov (United States)

    Hitchon, W. N. G.

    1999-01-01

    Plasma processing is a central technique in the fabrication of semiconductor devices. This self-contained book provides an up-to-date description of plasma etching and deposition in semiconductor fabrication. It presents the basic physics and chemistry of these processes, and shows how they can be accurately modeled. The author begins with an overview of plasma reactors and discusses the various models for understanding plasma processes. He then covers plasma chemistry, addressing the effects of different chemicals on the features being etched. Having presented the relevant background material, he then describes in detail the modeling of complex plasma systems, with reference to experimental results. The book closes with a useful glossary of technical terms. No prior knowledge of plasma physics is assumed in the book. It contains many homework exercises and serves as an ideal introduction to plasma processing and technology for graduate students of electrical engineering and materials science. It will also be a useful reference for practicing engineers in the semiconductor industry.

  4. Nippon paint atmospheric plasma system

    International Nuclear Information System (INIS)

    An invitational plasma systems which are able to generate the wide and stable plasma (discharge distance 30 cm length, discharge electrode length max. 16 m) under normal air and pressure by using and narrow wave-form of pulse voltage has been developed. Its technical outline and some applied examples are reported

  5. Physics of Space Plasma Activity

    International Nuclear Information System (INIS)

    This book provides a timely review of our present understanding of plasma phenomena in magnetized terrestrial and solar space plasmas. The author's emphasis is on the fluid and particle modeling and interpretation of observed active processes in space plasmas, i.e. 'the physical background of large plasma eruptions in space'. It is somewhat alarming for a plasma physicist to read that an emphasis on processes in spatially inhomogeneous plasmas means that the work '... excludes a considerable fraction of the available methods in space plasma physics, such as the theory of waves, instabilities and wave particle interactions on a homogeneous background', particularly in light of the fact that much of our knowledge of these plasmas is derived from observations of such waves. However, it is clear on reading the book that such a restriction is not a disadvantage, but allows the author to concentrate on the main theme of the book, namely the use of fluid and particle pictures to model the equilibrium and active states of space plasmas. There are many other books which cover the wave aspects of space plasmas, and would complement this book. The book's coverage is based on the extensive and profound research of the author and his colleagues in the area of fluid and particle modeling of space plasma structures. After an introduction to the physical setting of active plasmas, and a necessarily concise, but effective, discussion of the fluid and particle models to be used, the steady states of the magnetized plasmas of interest are treated, including the magnetosphere, solar plasmas and current sheets. Next the dynamics of unstable states is covered, including MHD and tearing instabilities, and nonlinear aspects, with a detailed discussion of magnetic reconnection. Finally, the models are applied to magnetospheric and solar observations. The book is attractively written and produced, and this reviewer managed to find a minimum number of errors. A particularly attractive

  6. Plasma oscillation and isotope effect

    International Nuclear Information System (INIS)

    Superconducting isotropic crystal is presented by two subsystems in terms of anharmonic oscillation model. The superconducting energy gap below the phase transition temperature is deduced by the free electron plasma energy. The anisotropic nature of the materials is appeared by the superconducting gaps in x, y, z directions. The phase transition temperature-square plasma energy relation is established. The observed facts for high temperature superconductors are consistent with the plasma theory. The isotope phase transition temperature shift is connected with the plasma energy. The fixing temperature divided by the phase transition temperature is the function of the molecular mass divided by effective mass density. The phase transition temperature depends on the interaction parameter. The equations for mercury and MgB2 isotopes are given. The interaction parameters reduce with the phase transition temperature rise. The isotope distinctions in the superconducting lines are explained. The phonon mechanism is concluded to be special case of the plasma mechanism

  7. Plasma oscillation and isotope effect

    Energy Technology Data Exchange (ETDEWEB)

    Netesova, Nadezhda P. [M.V. Lomonosov Moscow State University, Physics Faculty, LTPS Department, Moscow 119992 (Russian Federation)], E-mail: npn@mig.phys.msu.ru

    2007-09-01

    Superconducting isotropic crystal is presented by two subsystems in terms of anharmonic oscillation model. The superconducting energy gap below the phase transition temperature is deduced by the free electron plasma energy. The anisotropic nature of the materials is appeared by the superconducting gaps in x, y, z directions. The phase transition temperature-square plasma energy relation is established. The observed facts for high temperature superconductors are consistent with the plasma theory. The isotope phase transition temperature shift is connected with the plasma energy. The fixing temperature divided by the phase transition temperature is the function of the molecular mass divided by effective mass density. The phase transition temperature depends on the interaction parameter. The equations for mercury and MgB{sub 2} isotopes are given. The interaction parameters reduce with the phase transition temperature rise. The isotope distinctions in the superconducting lines are explained. The phonon mechanism is concluded to be special case of the plasma mechanism.

  8. Plasma evolution in the heliosheath

    Science.gov (United States)

    Richardson, J. D.

    2011-12-01

    Voyager 2 is now at 97 AU probably about 20 AU deep into the heliosheath. The Plasma Science experiment provides the only direct observations of plasma in the heliosheath. The plasma parameters depend on many factors; the solar wind source, the motions of the termination shock, and the influence of the interstellar medium among them. I will present the most recent plasma observations. Plasma speeds observed at Voyager 2 have decreased slowly across the heliosheath and remain well above those inferred at Voyager 1. The Voyager 2 flow angles continue to increase with large flows in the T than N directions (RTN coordinates). The density and temperature have decreased across the heliosheath until the beginning of 2011; since then the density has increased by a factor of 2 and the speed and temperature have also increased.

  9. Plasma modelling and numerical simulation

    International Nuclear Information System (INIS)

    Plasma modelling is an exciting subject in which virtually all physical disciplines are represented. Plasma models combine the electromagnetic, statistical and fluid dynamical theories that have their roots in the 19th century with the modern insights concerning the structure of matter that were developed throughout the 20th century. The present cluster issue consists of 20 invited contributions, which are representative of the state of the art in plasma modelling and numerical simulation. These contributions provide an in-depth discussion of the major theories and modelling and simulation strategies, and their applications to contemporary plasma-based technologies. In this editorial review, we introduce and complement those papers by providing a bird's eye perspective on plasma modelling and discussing the historical context in which it has surfaced. (editorial review)

  10. Plasma treatment advantages for textiles

    CERN Document Server

    Sparavigna, Amelia

    2008-01-01

    The textile industry is searching for innovative production techniques to improve the product quality, as well as society requires new finishing techniques working in environmental respect. Plasma surface treatments show distinct advantages, because they are able to modify the surface properties of inert materials, sometimes with environment friendly devices. For fabrics, cold plasma treatments require the development of reliable and large systems. Such systems are now existing and the use of plasma physics in industrial problems is rapidly increasing. On textile surfaces, three main effects can be obtained depending on the treatment conditions: the cleaning effect, the increase of microroughness (anti-pilling finishing of wool) and the production of radicals to obtain hydrophilic surfaces. Plasma polymerisation, that is the deposition of solid polymeric materials with desired properties on textile substrates, is under development. The advantage of such plasma treatments is that the modification turns out to ...

  11. Plasma diagnostics and atomic processes

    International Nuclear Information System (INIS)

    Spectroscopic plasma diagnostics with the use of atomic processes are discussed relating to three subjects in the followings. i) Time resolved X-ray spectra of titanium helium-like ions from tokamaks. X-ray spectra observed from tokamak plasmas are analysed with a non-ionization equilibrium model which could explain the time behavior of both spectra and ion abundances. ii) Line intensity ratios of OV ions for temperature and density diagnostics. Intensity ratios of emission lines from OV ions are calculated for use in temperature and density diagnostics. The line emissions from a tokamak are analysed for the diagnostics of plasma periphery. iii) Collisional processes in hot dense plasmas. The collisional ladder-like excitation and ionization in a hot dense plasma are discussed for the dielectronic states. This process enhances the excitation rate coefficients and decreases the resonance contributions to the excitation cross section. (author)

  12. Arc Plasma Gun With Coaxial Powder Feed

    Science.gov (United States)

    Zaplatynsky, Isidor

    1988-01-01

    Redesigned plasma gun provides improved metallic and ceramic coatings. Particles injected directly through coaxial bore in cathode into central region of plasma jet. Introduced into hotter and faster region of plasma jet.

  13. COSMIC PLASMA DYNAMO

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new dynamo model based on the polarization of plasma is presented in this paper.From the Maxwell equations in a moving medium, a magnetization vector can be causedwith Rongon current. The steady solar magnetic field is solved from the equations. Onthe assumption that the meridianal flow is ignored, the distribution of magnetic field isput out. In the model, there is no additional parameter considered. The intensity ofmagnetic field inside the sun ranges from 1-6T. The surface magnetic field around thepole is in the order of 1×10-3T, at low latitude the calculated surface magnetic fieldhas the order of 1×10-2 T. The maximum magnetic field is around 30° in latitude.

  14. Solid state plasmas

    CERN Document Server

    Manfredi, Giovanni

    2014-01-01

    Magnetic fusion devices operate at regimes characterized by extremely high temperatures and low densities, for which the charged particles motion is well described by classical mechanics. This is not true, however, for solid-state metallic objects: their density approaches $10^{28} \\rm m^{-3}$, so that the average interparticle distance is shorter than the de Broglie wavelength, which characterizes the spread of the electron wave function. Under these conditions, the conduction electrons behave as a true quantum plasma even at room temperature. Here, we shall illustrate the impact of quantum phenomena on the electron dynamics in metallic objects of nanometric size, particularly thin metallic films excited by short laser pulses. Further, we will discuss more recent results on regimes that involve spin and relativistic effects.

  15. Waves in Space Plasmas

    International Nuclear Information System (INIS)

    Applications of linear mode conversion at Alfven/ion-ion hybrid resonances and at electron plasma frequency have been discussed. Alfven resonances play an important role on energy transport the outer to inner regions of magnetospheres. At Earth's magnetopause, the mode-converted kinetic Alfven waves also lead to solar wind particle entry and transverse ion heating. IIH resonant waves can explain of the generation of linearly polarized EMIC waves at Earth. Compressional waves can also interact with Mercury's magnetosphere exciting IIH resonances as global eigenmodes. Linear mode conversion (LMC) from Langmuir to electromagnetic waves is relevant to explain type II and III radio bursts. Through the LMC, both right- and left-hand polarized wave modes are produced and it provides the solutions for linear/partial polarized type II and III problems.

  16. Plasma focus neutron source

    International Nuclear Information System (INIS)

    A neutron source not permanently active is obtained from an electric discharge plasma focus (PF) device. A small PF device, a Mather model device, works in the limit of low energy, 100 to 200 J at charging voltage of 20 to 30 kV with a capacitor bank of 160 nF, and a characteristic inductance of 25 to 50 nH. A theoretical model leads us to estimate the optimum values of capacitance, inductance, initial charging voltage and electrode geometry. In this work is presented the design evolution and construction of a first PF neutron source prototype, preliminary measures of current, voltage and temporal evolution of the current with the end of have an electric characterization. This parameters must be optimized with the objective of geeting an emission of 104 to 105 neutrons per pulse when Deuterium is used like filled gas (C.W)

  17. NCSX Plasma Heating Methods

    Energy Technology Data Exchange (ETDEWEB)

    H.W. Kugel; D. Spong; R. Majeski; M. Zarnstorff

    2003-02-28

    The NCSX (National Compact Stellarator Experiment) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral-beam injection, and radio-frequency. Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The plan is to provide 3 MW of 50 keV balanced neutral-beam tangential injection with pulse lengths of 500 msec for initial experiments, and to be upgradeable to pulse lengths of 1.5 sec. Subsequent upgrades will add 3 MW of neutral-beam injection. This Chapter discusses the NCSX neutral-beam injection requirements and design issues, and shows how these are provided by the candidate PBX-M (Princeton Beta Experiment-Modification) neutral-beam injection system. In addition, estimations are given for beam-heating efficiencies, scaling of heating efficiency with machine size an d magnetic field level, parameter studies of the optimum beam-injection tangency radius and toroidal injection location, and loss patterns of beam ions on the vacuum chamber wall to assist placement of wall armor and for minimizing the generation of impurities by the energetic beam ions. Finally, subsequent upgrades could add an additional 6 MW of radio-frequency heating by mode-conversion ion-Bernstein wave (MCIBW) heating, and if desired as possible future upgrades, the design also will accommodate high-harmonic fast-wave and electron-cyclotron heating. The initial MCIBW heating technique and the design of the radio-frequency system lend themselves to current drive, so that if current drive became desirable for any reason only minor modifications to the heating system described here would be needed. The radio-frequency system will also be capable of localized ion heating (bulk or tail), and possibly ion-Bernstein-wave-generated sheared flows.

  18. Plasma Beat-Wave Acceleration

    Science.gov (United States)

    Clayton, Christopher E.

    2002-04-01

    Among all the advanced accelerator concepts that use lasers as the power source, most of the effort to date has been with the idea of using a laser pulse to excite a accelerating mode in a plasma. Within this area, there are a variety of approaches for creating the accelerating mode, as indicated by the other talks in this session. What is common to these approaches is the physics of how a laser pulse pushes on plasma electrons to organize electron-density perturbations, the sources of the ultra-high (> GeV/M) accelerating gradients. It is the "ponderomotive force", proportional to the local gradient of the of the laser intensity, that pushes plasma electrons forward (on the leading edge of the pulse) and backwards (on the trailing edge) which leads to harmonic motion of the electrons. As the laser pulse moves through the plasma at group velocity Vg c, the oscillating electrons show up macroscopically as a plasma mode or wave with frequency w equal to the plasma frequency and k = w/Vg. For short laser pulses, this is the Laser Wakefield Accelerator (LWFA) concept. Closely related is the Plasma Beat-Wave Acceleration (PBWA) concept. Here, the laser pulse that perturbs the plasma is composed of two closely-spaced frequencies that "beat", i.e., periodically constructively and destructively interfere, forming an electromagnetic beat wave. One can visualize this as a train of short pulses. If this beating frequency is set to the plasma frequency, then each pulse in the train will reinforce the density perturbation caused by the previous pulse. The principal advantage of multiple pulses driving up the plasma wave as opposed to a single pulse is in efficiency, allowing for the production of relatively large diameter (more 1-D like) accelerating modes. In this talk I will discuss past, current and planned PBWA experiments which are taking place at UCLA, RAL in England, and LULI in France.

  19. Experimental plasma research project summaries

    International Nuclear Information System (INIS)

    This is the latest in a series of Project Summary books going back to 1976 and is the first after a hiatus of several years. They are published to provide a short description of each project supported by the Experimental Plasma Research Branch of the Division of Applied Plasma Physics in the Office of Fusion Energy. The Experimental Plasma Research Branch seeks to provide a broad range of experimental data, physics understanding, and new experimental techniques that contribute to operation, interpretation, and improvement of high temperature plasma as a source of fusion energy. In pursuit of these objectives, the branch supports research at universities, DOE laboratories, other federal laboratories and industry. About 70 percent of the funds expended are spent at universities and a significant function of this program is the training of students in fusion physics. The branch supports small- and medium-scale experimental studies directly related to specific critical plasma issues of the magnetic fusion program. Plasma physics experiments are conducted on transport of particles and energy within plasma and innovative approaches for operating, controlling, and heating plasma are evaluated for application to the larger confinement devices of the magnetic fusion program. New diagnostic approaches to measuring the properties of high temperature plasmas are developed to the point where they can be applied with confidence on the large-scale confinement experiments. Atomic data necessary for impurity control, interpretation of diagnostic data, development of heating devices, and analysis of cooling by impurity ion radiation are obtained. The project summaries are grouped into these three categories of plasma physics, diagnostic development and atomic physics

  20. Aerospace applications of pulsed plasmas

    Science.gov (United States)

    Starikovskiy, Andrey

    2012-10-01

    The use of a thermal equilibrium plasma for combustion control dates back more than a hundred years to the advent of internal combustion (IC) engines and spark ignition systems. The same principles are still applied today to achieve high efficiency in various applications. Recently, the potential use of nonequilibrium plasma for ignition and combustion control has garnered increasing interest due to the possibility of plasma-assisted approaches for ignition and flame stabilization. During the past decade, significant progress has been made toward understanding the mechanisms of plasma chemistry interactions, energy redistribution and the nonequilibrium initiation of combustion. In addition, a wide variety of fuels have been examined using various types of discharge plasmas. Plasma application has been shown to provide additional combustion control, which is necessary for ultra-lean flames, high-speed flows, cold low-pressure conditions of high-altitude gas turbine engine (GTE) relight, detonation initiation in pulsed detonation engines (PDE) and distributed ignition control in homogeneous charge-compression ignition (HCCI) engines, among others. The present paper describes the current understanding of the nonequilibrium excitation of combustible mixtures by electrical discharges and plasma-assisted ignition and combustion. Nonequilibrium plasma demonstrates an ability to control ultra-lean, ultra-fast, low-temperature flames and appears to be an extremely promising technology for a wide range of applications, including aviation GTEs, piston engines, ramjets, scramjets and detonation initiation for pulsed detonation engines. To use nonequilibrium plasma for ignition and combustion in real energetic systems, one must understand the mechanisms of plasma-assisted ignition and combustion and be able to numerically simulate the discharge and combustion processes under various conditions.

  1. Revisiting the plasma sheath - dust in plasma sheath

    CERN Document Server

    Das, G C; Bora, M P

    2015-01-01

    In this work, we have considered the formation of warm plasma sheath in the vicinity of a wall in a plasma with considerable presence of dust particles. As an example, we have used the parameters relevant in case of lunar plasma sheath, though the results obtained in this work could be applied to any other physical situation such as laboratory plasma. In the ion-acoustic time scale, we neglect the dust dynamics. The dust particles affect the sheath dynamics by affecting the Poisson equation which determines the plasma potential in the sheath region. We have assumed the current to a dust particle to be balanced throughout the analysis. This makes the grain potential dependent on plasma potential, which is then incorporated into the Poisson equation. The resultant numerical model becomes an initial value problem, which is described by a 1-D integro-differential equation, which is then solved self-consistently by incorporating the change in plasma potential caused by inclusion of the dust potential in the Poisso...

  2. Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

    Science.gov (United States)

    Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

    2013-10-01

    A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

  3. Range of fractionated plasma products to optimize plasma resources

    Institute of Scientific and Technical Information of China (English)

    Thierry Burnouf

    2010-01-01

    @@ HUMAN PLASMA is a source material that is crucial for the production of unique therapeutic fractionated products. Indeed, plasma contains hundreds of proteins ensuring many physiological functions. The most abun-dant proteins, albumin and immunoglobulin G (IgG) ,are present at about 35 and 10 g/L,respectively,repre-senting about 80% of all plasma proteins. However,other important therapeutic proteins include the coagu-lation factors (factor Ⅷ (F Ⅷ) ; FIX ; Von Willebrand Factor (VWF), fibrinogen) various protease inhibitors (alpha 1-antitrypsin ; antithrombin; C1-esterase) and anticoagulants (protein C) which exhibit potent physi-ological activity.

  4. Laser Plasmas : Optical guiding of laser beam in nonuniform plasma

    Indian Academy of Sciences (India)

    Tarsem Singh Gill

    2000-11-01

    A plasma channel produced by a short ionising laser pulse is axially nonuniform resulting from the self-defocusing. Through such preformed plasma channel, when a delayed pulse propagates, the phenomena of diffraction, refraction and self-phase modulation come into play. We have solved the nonlinear parabolic partial differential equation governing the propagation characteristics for an approximate analytical solution using variational approach. Results are compared with the theoretical model of Liu and Tripathi (Phys. Plasmas 1, 3100 (1994)) based on paraxial ray approximation. Particular emphasis is on both beam width and longitudinal phase delay which are crucial to many applications.

  5. Controlled fusion and plasma physics

    International Nuclear Information System (INIS)

    40 papers are presented at this 21. conference on controlled fusion and plasma physics (JET). Titles are: effects of sawtooth crashes on beams ions and fusion product tritons; beta limits in H-modes and VH-modes; impurity induced neutralization of MeV energy protons in JET plasmas; lost α particle diagnostic for high-yield D-T fusion plasmas; 15-MeV proton emission from ICRF-heated plasmas; pulse compression radar reflectometry for density measurements; gamma-ray emission profile measurements during ICRH discharges; the new JET phase ICRH array; simulation of triton burn-up; parametric dependencies of JET electron temperature profiles; detached divertor plasmas; excitation of global Alfven Eigenmodes by RF heating; mechanisms of toroidal rotation; effect of shear in the radial electric field on confinement; plasma transport properties at the L-H transition; numerical study of plasma detachment conditions in JET divertor plasmas; the SOL width and the MHD interchange instability; non linear magnetic reconnection in low collisionality plasmas; topology and slowing down of high energy ion orbits; sawtooth crashes at high beta; fusion performances and alpha heating in future JET D-T plasmas; a stable route to high-beta plasmas with non-monotonic q-profiles; theory of propagation of changes to confinement; spatial distribution of gamma emissivity and fast ions during ICRF heating; multi-camera soft X-ray diagnostic; radiation phenomena and particle fluxes in the X-event; local measurement of transport parameters for laser injected trace impurities; impurity transport of high performance discharges; negative snakes and negative shear; neural-network charge exchange analysis; ion temperature anisotropy in helium neutral beam fuelling; impurity line emission due to thermal charge exchange in edge plasmas; control of convection by fuelling and pumping; VH mode accessibility and global H-mode properties; ion cyclotron emission by spontaneous emission; LHCD/ICRH synergy

  6. Plasma Nanoscience: from Nano-Solids in Plasmas to Nano-Plasmas in Solids

    CERN Document Server

    Ostrikov, K; Meyyappan, M

    2013-01-01

    The unique plasma-specific features and physical phenomena in the organization of nanoscale solid-state systems in a broad range of elemental composition, structure, and dimensionality are critically reviewed. These effects lead to the possibility to localize and control energy and matter at nanoscales and to produce self-organized nano-solids with highly unusual and superior properties. A unifying conceptual framework based on the control of production, transport, and self-organization of precursor species is introduced and a variety of plasma-specific non-equilibrium and kinetics-driven phenomena across the many temporal and spatial scales is explained. When the plasma is localized to micrometer and nanometer dimensions, new emergent phenomena arise. The examples range from semiconducting quantum dots and nanowires, chirality control of single-walled carbon nanotubes, ultra-fine manipulation of graphenes, nano-diamond, and organic matter, to nano-plasma effects and nano-plasmas of different states of matter...

  7. Control of reactive plasmas in a multicusp plasma source equipped with a movable magnetic filter

    OpenAIRE

    Fukumasa, Osamu; Naitou, Hiroshi; Sakiyama, Satoshi

    1993-01-01

    With the use of both a movable magnetic filter and a plasma grid, plasma parameters (H2-CH4 or Ar-CH4 plasmas) are spatially well controlled. At any filter position, plasma parameters change steeply across the magnetic filter. Then, a plasma source is divided into the two parts, i.e., the source plasma region (high density plasma with energetic electrons) and the diffused plasma region (low density and low-temperature plasma without energetic electrons). Plasma parameters in the diffused plas...

  8. BOOK REVIEW: Kinetic theory of plasma waves, homogeneous plasmas

    Science.gov (United States)

    Porkolab, Miklos

    1998-11-01

    The linear theory of plasma waves in homogeneous plasma is arguably the most mature and best understood branch of plasma physics. Given the recently revised version of Stix's excellent Waves in Plasmas (1992), one might ask whether another book on this subject is necessary only a few years later. The answer lies in the scope of this volume; it is somewhat more detailed in certain topics than, and complementary in many fusion research relevant areas to, Stix's book. (I am restricting these comments to the homogeneous plasma theory only, since the author promises a second volume on wave propagation in inhomogeneous plasmas.) This book is also much more of a theorist's approach to waves in plasmas, with the aim of developing the subject within the logical framework of kinetic theory. This may indeed be pleasing to the expert and to the specialist, but may be too difficult to the graduate student as an `introduction' to the subject (which the author explicitly states in the Preface). On the other hand, it may be entirely appropriate for a second course on plasma waves, after the student has mastered fluid theory and an introductory kinetic treatment of waves in a hot magnetized `Vlasov' plasma. For teaching purposes, my personal preference is to review the cold plasma wave treatment using the unified Stix formalism and notation (which the author wisely adopts in the present book, but only in Chapter 5). Such an approach allows one to deal with CMA diagrams early on, as well as to provide a framework to discuss electromagnetic wave propagation and accessibility in inhomogeneous plasmas (for which the cold plasma wave treatment is perfectly adequate). Such an approach does lack some of the rigour, however, that the author achieves with the present approach. As the author correctly shows, the fluid theory treatment of waves follows logically from kinetic theory in the cold plasma limit. I only question the pedagogical value of this approach. Otherwise, I welcome this

  9. Plasma technology in metallurgical processing

    Energy Technology Data Exchange (ETDEWEB)

    Haile, O.

    1995-12-31

    This literature work is mainly focusing on the mechanisms of plasma technology and telling about metallurgical processing, particularly iron and steelmaking as well as the advantage of the unique properties of plasma. The main advantages of plasma technology in metallurgical operations is to direct utilization of naturally available raw materials and fuels without costly upgrading andlor beneficiation, improved environmental impact, improve process control, significant amplification of reactor and process equipment utilization and increased efficiency of raw materials, energy and man power. This literature survey is based on the publication `plasma technology in metallurgical processing` presents a comprehensive account of the physical, electrical, and mechanical aspects of plasma production and practical processing. The applications of plasma technology in metallurgical processing are covered in depth with special emphasis on developments in promising early stages. Plasma technology of today is mature in the metallurgical process applications. A few dramatic improvements are expected in the near future this giving an impetus to the technologists for the long range planning. (18 refs.) (author)

  10. Stability analysis of tokamak plasmas

    International Nuclear Information System (INIS)

    In a tokamak plasma, the energy transport is mainly turbulent. In order to increase the fusion reactions rate, it is needed to improve the energy confinement. The present work is dedicated to the identification of the key parameters leading to plasmas with a better confined energy in order to guide the future experiments. For this purpose, a numerical code has been developed. It calculates the growth rates characterizing the instabilities onset. The stability analysis is completed by the evaluation of the shearing rate of the rotation due to the radial electric field. When this shearing rate is greater than the growth rate the ion turbulence is fully stabilised. The shearing rate and the growth rate are determined from the density, temperature and security factor profiles of a given plasma. Three types of plasmas have been analysed. In the Radiative Improved modes of TEXTOR, high charge number ions seeding lowers the growth rates. In Tore Supra-high density plasmas, a strong magnetic shear and/or a more efficient ion heating linked to a bifurcation of the toroidal rotation direction (which is not understood) trigger the improvement of the confinement. In other Tore Supra plasmas, locally steep electron pressure gradients have been obtained following magnetic shear reversal. This locally negative magnetic shear has a stabilizing effect. In these three families of plasmas, the growth rates decrease, the confinement improves, the density and temperature profiles are steeper. This steepening induces an increase of the rotation shearing rate, which then maintains the confinement high quality. (author)

  11. Cold plasma decontamination of foods.

    Science.gov (United States)

    Niemira, Brendan A

    2012-01-01

    Cold plasma is a novel nonthermal food processing technology that uses energetic, reactive gases to inactivate contaminating microbes on meats, poultry, fruits, and vegetables. This flexible sanitizing method uses electricity and a carrier gas, such as air, oxygen, nitrogen, or helium; antimicrobial chemical agents are not required. The primary modes of action are due to UV light and reactive chemical products of the cold plasma ionization process. A wide array of cold plasma systems that operate at atmospheric pressures or in low pressure treatment chambers are under development. Reductions of greater than 5 logs can be obtained for pathogens such as Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. Effective treatment times can range from 120 s to as little as 3 s, depending on the food treated and the processing conditions. Key limitations for cold plasma are the relatively early state of technology development, the variety and complexity of the necessary equipment, and the largely unexplored impacts of cold plasma treatment on the sensory and nutritional qualities of treated foods. Also, the antimicrobial modes of action for various cold plasma systems vary depending on the type of cold plasma generated. Optimization and scale up to commercial treatment levels require a more complete understanding of these chemical processes. Nevertheless, this area of technology shows promise and is the subject of active research to enhance efficacy. PMID:22149075

  12. ITER plasma-facing components

    Energy Technology Data Exchange (ETDEWEB)

    Merola, Mario, E-mail: mario.merola@iter.or [ITER Organization, CS 90 046, 13067 St Paul-lez-Durance Cedex (France); Loesser, D. [Blanket Integrated Product Team, Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Martin, A.; Chappuis, P.; Mitteau, R.; Komarov, V.; Pitts, R.A.; Gicquel, S.; Barabash, V.; Giancarli, L.; Palmer, J.; Nakahira, M.; Loarte, A.; Campbell, D.; Eaton, R.; Kukushkin, A.; Sugihara, M.; Zhang, F.; Kim, C.S.; Raffray, R. [ITER Organization, CS 90 046, 13067 St Paul-lez-Durance Cedex (France)

    2010-12-15

    The ITER plasma-facing components directly face the thermonuclear plasma and include the divertor, the blanket and the test blanket modules with their corresponding frames. The divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimising the helium and impurity content in the plasma. The blanket system provides a physical boundary for the plasma transients and contributes to the thermal and nuclear shielding of the vacuum vessel and external machine components. It consists of modular shielding elements known as blanket modules which are attached to the vacuum vessel. Each blanket module consists of two major components: a plasma-facing first wall panel and a shield block. The test blanket modules are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to test blanket modules, each of them providing for the allocation of two breeding modules inserted in a steel frame and in front of a shield block.

  13. ITER plasma-facing components

    International Nuclear Information System (INIS)

    The ITER plasma-facing components directly face the thermonuclear plasma and include the divertor, the blanket and the test blanket modules with their corresponding frames. The divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimising the helium and impurity content in the plasma. The blanket system provides a physical boundary for the plasma transients and contributes to the thermal and nuclear shielding of the vacuum vessel and external machine components. It consists of modular shielding elements known as blanket modules which are attached to the vacuum vessel. Each blanket module consists of two major components: a plasma-facing first wall panel and a shield block. The test blanket modules are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to test blanket modules, each of them providing for the allocation of two breeding modules inserted in a steel frame and in front of a shield block.

  14. Special issue on transient plasmas

    Science.gov (United States)

    Bailey, James; Hoarty, David; Mancini, Roberto; Yoneda, Hitoki

    2015-11-01

    This special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is dedicated to the "spectroscopy of transient plasmas" covering plasma conditions produced by a range of pulsed laboratory sources including short and long pulse lasers, pulsed power devices, and free electron lasers (FELs). The full range of plasma spectroscopy up to high energy bremsstrahlung radiation, including line broadening analysis for application to data recorded with the ChemCam instrument on the Mars Science Laboratory rover Curiosity, is covered. This issue is timely as advances in optical lasers and x-ray FELs (XFEL) are enabling transient plasma to be probed at higher energies and shorter durations than ever before. New XFEL facilities being commissioned in Europe and Asia are adding to those operating in the US and Japan and the ELI high power laser project in Europe, due to open this year, will provide short pulse lasers of unprecedented power. This special issue represents a snapshot of the theoretical and experimental research in dense plasmas, electron kinetics, laser-induced breakdown spectroscopy of low temperature plasmas, inertial confinement fusion and non-equilibrium atomic physics using spectroscopy to diagnose plasmas produced by optical lasers, XFELs and pulsed-power machines.

  15. Plasma Treatments and Biomass Gasification

    International Nuclear Information System (INIS)

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

  16. Laser-induced plasma temperature

    International Nuclear Information System (INIS)

    It is of great importance to explore the evolution of laser-induced plasma (LIP) properties, especially plasma temperature, with regard to variations of experiment conditions in both theoretical study and routine applications. By investigating the influence of various factors on plasma temperature, one can gain knowledge about the processes in plasma and adjust experimental conditions to obtain optimum analytical performance. Herein the fundamental theories and calculation methods of LIP temperature via spectroscopic approaches are briefly reviewed. Its temporal and spatial evolutions together with several influencing factors are discussed, such as laser parameters, ambient surrounding, and physical and chemical properties of the sample. The results summarized exhibit the general trend that LIP temperature increases with increasing laser wavelength, pulse width, laser energy, background gas pressure, and sample hardness. On the other hand, it decreases with time elapsing and distance from sample surface. Moreover, plasma temperature generated in argon surrounding is higher than that in other gas species, and the rank of temperature values generated from different samples exhibits a general tendency of Cu > Fe > Ni ≈ Al ≈ glass ≈ rock. Additionally, LIP temperature tends to increase as lens focal point approaches sample surface, and the plasma confinement effect in sample cavity is significant in altering plasma temperature. Various explanations are given to interpret these temperature behaviors. - Highlights: • Fundamental theories and calculation methods of LIP temperature are reviewed. • Influences of various factors on LIP temperature are discussed. • Various explanations are given to interpret the temperature behaviors

  17. Modeling the Europa plasma torus

    Science.gov (United States)

    Schreier, Ron; Eviatar, Aharon; Vasyliunas, Vytenis M.; Richardson, John D.

    1993-01-01

    The existence of a torus of plasma generated by sputtering from Jupiter's satellite Europa has long been suspected but never yet convincingly demonstrated. Temperature profiles from Voyager plasma observations indicate the presence of hot, possibly freshly picked-up ions in the general vicinity of the orbit of Europa, which may be interpreted as evidence for a local plasma torus. Studies of ion partitioning in the outer regions of the Io torus reveal that the oxygen to sulfur mixing ratio varies with radial distance; this may indicates that oxygen-rich matter is injected from a non-Io source, most probably Europa. We have constructed a quantitative model of a plasma torus near the orbit of Europa which takes into account plasma input from the Io torus, sputtering from the surface of Europa, a great number of ionization and charge exchange processes, and plasma loss by diffusive transport. When the transport time is chosen so that the model's total number density in consistent with the observed total plasma density, the contribution from Europa is found to be significant although not dominant. The model predicts in detail the ion composition, charge states, and the relative fractions of hot Europa-generated and (presumed) cold Io-generated ions. The results are generally consistent with observations from Voyager and can in principle (subject to limitations of data coverage) be confirmed in more detail by Ulysses.

  18. Couette Flow of Unmagnetized Plasma

    CERN Document Server

    Collins, C; Cooper, C M; Flanagan, K; Khalzov, I V; Nornberg, M D; Seidlitz, B; Wallace, J; Forest, C B

    2014-01-01

    Differentially rotating flows of unmagnetized, highly conducting plasmas have been created in the Plasma Couette Experiment. Previously, hot-cathodes have been used to control plasma rotation by a stirring technique [C. Collins et al., Phys. Rev. Lett. 108, 115001(2012)] on the outer cylindrical boundary---these plasmas were nearly rigid rotors, modified only by the presence of a neutral particle drag. Experiments have now been extended to include stirring from an inner boundary, allowing for generalized Couette flow and opening a path for both hydrodynamic and magnetohydrodynamic experiments, as well as fundamental studies of plasma viscosity. Plasma is confined in a cylindrical, axisymmetric, multicusp magnetic field, with $T_e< 10$ eV, $T_i<1$ eV, and $n_e<10^{11}$ cm$^{-3}$. Azimuthal flows (up to 12 km/s, $M=V/c_s\\sim 0.7$) are driven by edge ${\\bf J \\times B}$ torques in helium, neon, argon, and xenon plasmas. We present measurements of a self-consistent, rotation-induced, species-dependent rad...

  19. Plasma opening switch conduction scaling

    International Nuclear Information System (INIS)

    Plasma opening switch (POS) experiments performed on the Hawk generator [Commisso et al., Phys. Fluids B 4, 2368 (1992)] (750 kA, 1.2 μs) determine the dependence of the conduction current and conduction time on plasma density, electrode dimensions, and current rise rate. The experiments indicate that for a range of parameters, conduction is controlled by magnetohydrodynamic (MHD) distortion of the plasma, resulting in a low density region where opening can occur, possibly by erosion. The MHD distortion corresponds to an axial translation of the plasma center-of-mass by half the initial plasma length, leading to a simple scaling relation between the conduction current and time, and the injected plasma density and POS electrode dimensions that is applicable to a large number of POS experiments. For smaller currents and conduction times, the Hawk data suggest a non-MHD conduction limit that may correspond to electromagnetohydrodynamic (EMH) field penetration through the POS plasma. copyright 1995 American Institute of Physics

  20. Plasma medicine: an introductory review

    Science.gov (United States)

    Kong, M. G.; Kroesen, G.; Morfill, G.; Nosenko, T.; Shimizu, T.; van Dijk, J.; Zimmermann, J. L.

    2009-11-01

    This introductory review on plasma health care is intended to provide the interested reader with a summary of the current status of this emerging field, its scope, and its broad interdisciplinary approach, ranging from plasma physics, chemistry and technology, to microbiology, biochemistry, biophysics, medicine and hygiene. Apart from the basic plasma processes and the restrictions and requirements set by international health standards, the review focuses on plasma interaction with prokaryotic cells (bacteria), eukaryotic cells (mammalian cells), cell membranes, DNA etc. In so doing, some of the unfamiliar terminology—an unavoidable by-product of interdisciplinary research—is covered and explained. Plasma health care may provide a fast and efficient new path for effective hospital (and other public buildings) hygiene—helping to prevent and contain diseases that are continuously gaining ground as resistance of pathogens to antibiotics grows. The delivery of medically active 'substances' at the molecular or ionic level is another exciting topic of research through effects on cell walls (permeabilization), cell excitation (paracrine action) and the introduction of reactive species into cell cytoplasm. Electric fields, charging of surfaces, current flows etc can also affect tissue in a controlled way. The field is young and hopes are high. It is fitting to cover the beginnings in New Journal of Physics, since it is the physics (and non-equilibrium chemistry) of room temperature atmospheric pressure plasmas that have made this development of plasma health care possible.

  1. Plasma medicine: an introductory review

    International Nuclear Information System (INIS)

    This introductory review on plasma health care is intended to provide the interested reader with a summary of the current status of this emerging field, its scope, and its broad interdisciplinary approach, ranging from plasma physics, chemistry and technology, to microbiology, biochemistry, biophysics, medicine and hygiene. Apart from the basic plasma processes and the restrictions and requirements set by international health standards, the review focuses on plasma interaction with prokaryotic cells (bacteria), eukaryotic cells (mammalian cells), cell membranes, DNA etc. In so doing, some of the unfamiliar terminology-an unavoidable by-product of interdisciplinary research-is covered and explained. Plasma health care may provide a fast and efficient new path for effective hospital (and other public buildings) hygiene-helping to prevent and contain diseases that are continuously gaining ground as resistance of pathogens to antibiotics grows. The delivery of medically active 'substances' at the molecular or ionic level is another exciting topic of research through effects on cell walls (permeabilization), cell excitation (paracrine action) and the introduction of reactive species into cell cytoplasm. Electric fields, charging of surfaces, current flows etc can also affect tissue in a controlled way. The field is young and hopes are high. It is fitting to cover the beginnings in New Journal of Physics, since it is the physics (and non-equilibrium chemistry) of room temperature atmospheric pressure plasmas that have made this development of plasma health care possible.

  2. Plasma acceleration processes in an ablative pulsed plasma thruster

    International Nuclear Information System (INIS)

    Plasma acceleration processes in an ablative pulsed plasma thruster (APPT) were investigated. APPTs are space propulsion options suitable for microspacecraft, and have recently attracted much attention because of their low electric power requirements and simple, compact propellant system. The plasma acceleration mechanism, however, has not been well understood. In the present work, emission spectroscopy, high speed photography, and magnetic field measurements are conducted inside the electrode channel of an APPT with rectangular geometry. The successive images of neutral particles and ions give us a comprehensive understanding of their behavior under electromagnetic acceleration. The magnetic field profile clarifies the location where the electromagnetic force takes effect. As a result, it is shown that high density, ablated neutral gas stays near the propellant surface, and only a fraction of the neutrals is converted into plasma and electromagnetically accelerated, leaving the residual neutrals behind

  3. Nonlinear beam plasma interaction in plasma with a superthermal electrons

    International Nuclear Information System (INIS)

    The study of plasmas containing superthermal particles is very important to the understanding of space and astrophysical phenomena. The non-Maxwellian plasmas are also crucial to the understanding of space and astrophyisical plasma dynamics. The kappa-type distribution is used to model a high energy tail in the electron/ion distribution function. We have investigated the dynamics of small amplitude electrostatic solitary structures in a plasma consisting of superthermal electrons, ions and an electron beam. Solitary structures is investigated. The effect(s) of ion beam characteristics, as well as of superthermality of the background, have been studied numerically to trace their influence on solitary structures. The results of this investigation may be important for understanding the nonlinear structures in astrophysical and space environments. (author)

  4. Plasma spheroidization of nickel powders in a plasma reactor

    Indian Academy of Sciences (India)

    G Shanmugavelayutham; V Selvarajan

    2004-10-01

    Thermal spray coatings of surfaces with metal, alloy and ceramic materials for protection against corrosion, erosion and wear is an intense field of research. The technique involves injection of the powder into a plasma flame, melting, acceleration of the powder particles, impact and bonding with the substrate. Feedstock powders of metals, alloys and ceramics for thermal spray applications have to meet several requirements. Particle shape, size and its distribution, powder flow characteristics and density are the important factors to be considered in order to ensure high spray efficiency and better coating properties. For smooth and uniform feeding of powders into plasma jet, the powder particles have to be spherical in shape. High temperatures and steep temperatures present in thermal plasma is exploited to spheroidize particles in the present investigation. Nickel powder particles in the size range from 40–100 m were spheroidized using plasma processing. SEM and optical micrographs showed spherical shape of processed particles.

  5. Surface plasma source with saddle antenna radio frequency plasma generator.

    Science.gov (United States)

    Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R

    2012-02-01

    A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing. PMID:22380221

  6. Plasma diagnostics in large area plasma processing system

    International Nuclear Information System (INIS)

    A series of plasma diagnostic have been carried out in our large area plasma processing system which is based on a modulated electron-beam produced plasma. These discharges were created in both electrically conducting and insulated vacuum chambers operated in 30-120 mTorr of pure gases (argon, oxygen, and nitrogen). Langmuir probes, microwave transmission, mass spectrometry, and external current sensors show robust discharges were made over fairly wide parameter ranges resulting in plasma densities of 1-4x1011 cm-3 and temperature ranging from 0.2 eV for the molecular gases and 1.4 eV for argon. The effects of various experimental techniques, parameters, and contamination issues are discussed in detail

  7. Plasma-wall interaction studies using linear plasma devices

    International Nuclear Information System (INIS)

    Plasma-facing materials of DEMO reactor suffer continuously irradiation of deuterium, tritium, helium and energetic neutron fluxes at elevated temperature. Linear plasma devices have been operated in steady state to predict experimentally the structural change of plasma-facing materials and behaviors of hydrogen isotopes under severe circumstances of thermonuclear reactors. The authors have investigated the adsorption and desorption behavior of hydrogen isotopes on W and the effect of neutron and helium irradiation on it. In the present article, retention characteristics of W for hydrogen isotopes under irradiation of neutrons and the plasma including deuterium, helium and beryllium are explained. They have been obtained by experiments with TPE and PISCES-B linear machines, under the contract of Japan-US scientific and engineering cooperation. (author)

  8. Comparison of calorimetric plasma diagnostics in a plasma downstream reactor

    Energy Technology Data Exchange (ETDEWEB)

    Roth, C; Zuber, V; Sonnenfeld, A; Rudolf von Rohr, P [ETH Zurich, Institute of Process Engineering, Sonneggstrasse 3, 8092 Zurich (Switzerland); Bornholdt, S; Kersten, H, E-mail: roth@ipe.mavt.ethz.ch [Christian-Albrechts-Universitaet zu Kiel, Institute of Experimental and Applied Physics, Leibnizstr.19, 24098 Kiel (Germany)

    2011-03-09

    The energy influx in a non-equilibrium plasma in the afterglow of a plasma downstream reactor has been measured by two different calorimetric probe types. The radio frequency discharge is investigated for oxygen (10-100%)-argon (90-0%) mixtures at relatively high gas flow rates (750-3000 sccm) and pressures (100-350 Pa). The main process parameters influencing the energy influx are the plasma power, the system pressure and the total gas flow rate. Even though the size, geometry and material composition of the used probe types are different, comparable energy flux values are achieved. Depending on the process parameters, energy fluxes between around 100 and 3500 W m{sup -2} are found and the variation of the pressure and total gas flow rate suggests a highly flow-dependent plasma density distribution in the reactor.

  9. Atrial natriuretic peptides in plasma

    DEFF Research Database (Denmark)

    Goetze, Jens P; Holst Hansen, Lasse; Terzic, Dijana;

    2015-01-01

    Measurement of cardiac natriuretic peptides in plasma has gained a diagnostic role in the assessment of heart failure. Plasma measurement is though hampered by the marked instability of the hormones, which has led to the development of analyses that target N-terminal fragments from the prohormone....... These fragments are stable in plasma and represent surrogate markers of the actual natriuretic hormone. Post-translational processing of the precursors, however, is revealing itself to be a complex event with new information still being reported on proteolysis, covalent modifications, and amino acid...

  10. Vortex dynamics in inhomogeneous plasmas

    DEFF Research Database (Denmark)

    Naulin, V.; Juul Rasmussen, J.

    1999-01-01

    The dynamics of vortical structures in magnetized plasmas with nonuniform density is investigated numerically. In particular the dynamics of monopolar vortices is considered and the results are discussed in terms of the conservation of potential vorticity. It is found that individual vortex...... structures tend to transport density up the gradient in contrast to structures embedded in developed turbulence, which on the average will lead to a flattening of the density gradient. The role of vortical structures in connection with electrostatic plasma turbulence and the associated cross-field plasma...

  11. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Frandsen, Henrik Lund; Christensen, N J;

    1991-01-01

    -induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

  12. Controlled fusion and plasma physics

    International Nuclear Information System (INIS)

    This document presents the several speeches that took place during the 22nd European Physical Society conference on Controlled Fusion and Plasma Physics in Bournemouth, UK, between the 2nd and 7th July 1995. The talks deal with new experiments carried out on several tokamaks, particularly Tore Supra, concerning plasma confinement and fusion. Some information on specific fusion devices or tokamak devices is provided, as well as results of experiments concerning plasma instability. Separate abstracts were prepared for all the 31 papers in this volume. (TEC)

  13. Radiometric force in dusty plasmas

    CERN Document Server

    Ignatov, A M

    2000-01-01

    A radiofrequency glow discharge plasma, which is polluted with a certain number of dusty grains, is studied. In addition to various dusty plasma phenomena, several specific colloidal effects should be considered. We focus on radiometric forces, which are caused by inhomogeneous temperature distribution. Aside from thermophoresis, the role of temperature distribution in dusty plasmas is an open question. It is shown that inhomogeneous heating of the grain by ion flows results in a new photophoresis like force, which is specific for dusty discharges. This radiometric force can be observable under conditions of recent microgravity experiments.

  14. Cosmology in the plasma universe

    International Nuclear Information System (INIS)

    Space observations have opened the spectral regions of X-rays and γ-rays, which are produced by plasma processes. The Plasma Universe derived from observations in these regions is drastically different from the now generally accepted 'Visual Light Universe' based on visual light observations alone. Historically this transitions can be compared only to the transition from the geocentric to the heliocentric cosmology. The purpose of this paper is to discuss what criteria a cosmological theory must satisfy in order to be acceptable in the Plasma Universe. (author)

  15. Vortex dynamics in inhomogeneous plasmas

    DEFF Research Database (Denmark)

    Naulin, V.; Juul Rasmussen, J.

    The dynamics of vortical structures in magnetized plasmas with nonuniform density is investigated numerically. In particular the dynamics of monopolar vortices is considered and the results are discussed in terms of the conservation of potential vorticity. It is found that individual vortex...... structures tend to transport density up the gradient in contrast to structures embedded in developed turbulence, which on the average will lead to a flattening of the density gradient. The role of vortical structures in connection with electrostatic plasma turbulence and the associated cross-field plasma...

  16. Plasma tomography of higher resolution

    International Nuclear Information System (INIS)

    New microwave tomography scheme for plasma diagnostic is suggested - ray based diffraction tomography, which promises to reach a resolution, close to a diffraction limit. Besides, this scheme is less sensitive to the amplitude fluctuations as compared with traditional phase tomography. The method, which was suggested earlier for the ionosphere applications, can be helpful also for revealing of electron density inhomogeneities in a hot plasma. The algorithm, used for processing, is able to reveal small-scale plasma inhomogeneities of characteristic length, comparable with microwave wavelength, that is up to 1-3 cm. (author)

  17. Quantum Statistics of Nonideal Plasmas

    CERN Document Server

    Kremp, Dietrich; Kraeft, Wolf-Dietrich

    2005-01-01

    This book deals with the statistical theory of strongly coupled Coulomb systems. After an elementary introduction to the physics of nonideal plasmas, a presentation of the method of (nonequilibrium) Green's functions is given. On this basis, the dielectric, thermodynamic, transport, and relaxation properties are discussed systematically. Especially, the behavior of bound states in the surrounding plasma (lowering of the ionization energy), the ionization kinetics, and the equation of state of dense partially ionized hydrogen are each carefully investigated. Furthermore, generalized kinetic equations are derived which are also valid for short time scales. They are applied to ultra-fast processes and to plasmas in laser fields.

  18. Plasma Deposition of Amorphous Silicon

    Science.gov (United States)

    Calcote, H. F.

    1982-01-01

    Strongly adhering films of silicon are deposited directly on such materials as Pyrex and Vycor (or equivalent materials) and aluminum by a non-equilibrium plasma jet. Amorphous silicon films are formed by decomposition of silicon tetrachloride or trichlorosilane in the plasma. Plasma-jet technique can also be used to deposit an adherent silicon film on aluminum from silane and to dope such films with phosphorus. Ability to deposit silicon films on such readily available, inexpensive substrates could eventually lead to lower cost photovoltaic cells.

  19. Collective oscillations in a plasma

    CERN Document Server

    Akhiezer, A I; Polovin, R V; ter Haar, D

    2013-01-01

    International Series of Monographs in Natural Philosophy: Collective Oscillations in a Plasma, Volume 7 presents specific topics within the general field of radio waves propagation. This book contains five chapters that address the theory of linear oscillations in a plasma, the spectra of the eigen oscillations, and the mechanism of high-frequency heating. The opening chapters deal with the self-consistent fields; development of initial perturbation; dispersion permittivity tensor of a plasma in a magnetic field; effect of thermal motion of particles on low-frequency resonances; excitation of

  20. Wave turbulence in magnetized plasmas

    Directory of Open Access Journals (Sweden)

    S. Galtier

    2009-02-01

    Full Text Available The paper reviews the recent progress on wave turbulence for magnetized plasmas (MHD, Hall MHD and electron MHD in the incompressible and compressible cases. The emphasis is made on homogeneous and anisotropic turbulence which usually provides the best theoretical framework to investigate space and laboratory plasmas. The solar wind and the coronal heating problems are presented as two examples of application of anisotropic wave turbulence. The most important results of wave turbulence are reported and discussed in the context of natural and simulated magnetized plasmas. Important issues and possible spurious interpretations are also discussed.

  1. Controlled fusion and plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document presents the several speeches that took place during the 22nd European Physical Society conference on Controlled Fusion and Plasma Physics in Bournemouth, UK, between the 2nd and 7th July 1995. The talks deal with new experiments carried out on several tokamaks, particularly Tore Supra, concerning plasma confinement and fusion. Some information on specific fusion devices or tokamak devices is provided, as well as results of experiments concerning plasma instability. Separate abstracts were prepared for all the 31 papers in this volume. (TEC).

  2. Supersonic plasma jet interaction with gases and plasmas

    Czech Academy of Sciences Publication Activity Database

    Nicolai, P.; Stenz, C.; Tikhonchuk, V.; Ribeyre, X.; Kasperczuk, A.; Pisarczyk, T.; Juha, Libor; Krouský, Eduard; Mašek, Karel; Pfeifer, Miroslav; Rohlena, Karel; Skála, Jiří; Ullschmied, Jiří; Kálal, M.; Klír, D.; Kravárik, J.; Kubeš, P.; Pisarczyk, P.

    2009-01-01

    Roč. 322, 1-4 (2009), 11-17. ISSN 0004-640X R&D Projects: GA MŠk(CZ) LC528; GA MŠk LA08024 Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z20430508 Keywords : supersonic plasma jet * laser experiment * shock Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.404, year: 2009

  3. Plasma Physics. Lectures Presented at the Seminar on Plasma Physics

    International Nuclear Information System (INIS)

    The International Seminar on Plasma Physics held in Trieste during 5- 1 October 1964 was the first major activity of the International Atomic Energy Agency's new International Centre for Theoretical Physics. In bringing together plasma physicists belonging to three distinct schools, the American, West European and the Soviet schools, the Seminar provided a unique opportunity for extended contacts between physicists in this field. It is hoped that these Proceedings will be of permanent value in the literature of the subject

  4. Plasma Post Oxidation of Plasma Nitrocarburized SKD 61 Steel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel. Plasma nitrocarburizing was conducted for 12 h at 540℃ in the nitrogen,hydrogen and methane atmosphere to produce the ε-Fe,2-3(N,C) phase. The compound layer produced by plasma nitrocarburising was predominantly composed of ε-phase, with a small proportion of γ′-Fe4(N,C) phase.The thickness of the compound layer and the diffusion layer are about 10 μm and about 200μm, respectively.Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of 500℃ for 1 h. The very thin magnetite (Fe3O4) layer of 1-2μm in thickness on top of the compound layer was obtained. Anodic polarization test revealed that plasma nitrocarburizing process contributed a significant improvement of corrosion resistance of SKD 61 steel. However, the corrosion characteristics of the nitrocarburized compound layer was deteriorated by oxidation treatment.

  5. The quark gluon plasma

    International Nuclear Information System (INIS)

    The quark-gluon plasma (QGP) is a state of matter in which the universe was expected to be a few micro-seconds after the big-bang. Violent collisions of heavy ions are supposed to re-create this state in particle accelerators. Numerous signatures of this fugacious state have already been observed at the RHIC (relativistic heavy ion collider). The first evidence of the violence of collisions is the number of generated particles: about 6000 per collision, mostly hadrons. This figure seems high but in fact is less than theoretically expected and is the first sign of the formation of a QGP that saturates the density of gluons. Another sign, observed at the RHIC is the damping of the particle jets that are produced in the collision. This damping is consistent with the crossing of a medium whose density is so high that it can not be made of hadrons but of partons. In the RHIC experiments the collective behaviour of quarks and gluons shows that they are strongly interacting with one another. This fact supports the idea that the QGP is more a perfect liquid rather than an ideal gas in which quarks and gluons move freely. (A.C.)

  6. Positron driven plasma wakefields

    Science.gov (United States)

    Pinkerton, S.; Shi, Y.; Huang, C.; An, W.; Mori, W. B.; Muggli, P.

    2010-11-01

    The LHC is producing high-energy, high-charge proton bunches (1e11 protons at 1-7 TeV each) that could be used to accelerate ``witness'' electron bunches to TeV range eneregies via a plasma wakefield accelerator (PWFA). Simulations [1] suggest that a proton ``drive'' bunch is able to excite large wakefields if the bunch size is on the order of 100 μm; however, the LHC paramters are currently on the 1 cm scale. SLAC'S FACET is able to supply positorn bunchs with the ideal parameters for driving a PWFA. Although at lower energy (2e10 positrons at 23 GeV each), initial simiulations in QuickPIC show that the physics of a positron drive bunch is very similar to that of a proton drive bunch. Differences in the physics arise from the mass difference: slower dephasing but faster transverse bunch evolution. Other considerations include driver head erosion and purity of the wakefield ion column. The physics of positive drivers for PWFA and the viability of this scheme for future high-energy colliders will be investigated at SLAC's FACET.[4pt] [1] Caldwell, et al. Nature Physics 5, 363 (2009).[0pt] [2] C.H. Huang, et al., J. Comp. Phys., 217(2), 658, (2006).

  7. The Mars Plasma Environment

    CERN Document Server

    Russell, C. T

    2007-01-01

    Mars sits very exposed to the solar wind and, because it is a small planet, has but a weak hold on its atmosphere. The solar wind therefore plays an important role in the evolution of the martian atmosphere. Over the last four decades a series of European missions, first from the Soviet Union and more recently from the European Space Agency, together with a single investigation from the U.S., the Mars Global Surveyor spacecraft, have added immeasurably to our understanding of the interplay between the solar wind and Mars atmosphere. Most recently the measurements of the plasma and fast neutral populations, conducted on the Mars Express spacecraft by the ASPERA-3 instrument have been acquired and analyzed. Their presentation to the public, most notably at the workshop "The Solar Wind Interaction and Atmosphere Evolution of Mars" held in Kiruna in early 2006, was the inspiration for this series of articles. However participation in the Kiruna conference was not a selection criterion for this volume. The papers ...

  8. PlasmaLab/EkoPlasma - The Future of Complex Plasma Research in Space

    Science.gov (United States)

    Knapek, Christina; Fortov, Vladimir; Huber, Peter; Mohr, Daniel; Konopka, Uwe; Lipaev, Andrey; Molotkov, Vladimir; Petrov, Oleg; Zähringer, Erich; Thomas, Hubertus

    2016-07-01

    The PlasmaLab project, a Russian-German cooperation, has the aim to develop a future laboratory for the investigation of complex plasmas under microgravity conditions on the International Space Station (ISS). Within the project, a new plasma chamber, the Zyflex chamber, has been developed and is now being prepared to be launched to the ISS in 2020 as a laboratory setup with the name EkoPlasma (Experiment komplex Plasma). The Zyflex chamber is a large, cylindrical plasma chamber with parallel, rf-driven electrodes and a flexible inner geometry. It is designed to extend the accessible experimental parameter range and to allow an independent control of the plasma parameters, therefore increasing the experimental possibilities and expected knowledge gain significantly. Further, a 3D optical diagnostic will allow for the study of particle dynamics in 3D realtime. Possible future research topics include e.g. phase transitions, the dynamics of liquids, phase separation, or turbulence. The experimental setup will be presented, as well as some preliminary results of experiments on earth and in parabolic flights to visualize the possibilities of this new laboratory. This work and some of the authors are funded by DLR/BMWi (FKZ 50WM1441).

  9. Miniature Flat Plasma Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This phase I SBIR project will develop a micromachined charged particle energy collimator plate to be used as a principle component in a micromachined plasma...

  10. Particle Acceleration in Underdense Plasmas

    CERN Document Server

    Pocsai, Mihály András; Varró, Sándor

    2014-01-01

    An effective theory of laser--plasma based particle acceleration is presented. Here we treated the plasma as a continuous medium with an index of refraction $n_{m}$ in which a single electron propagates. Because of the simplicity of this model, we did not need to perform PIC simulations in order to study the properties of the electron acceleration. We studied the properties of the electron motion due to the Lorentz force and the relativistic equations of motion were numerically solved and analysed. We found that if the plasma density is much below the critical density then the acceleration of the electrons in plasma $(n_{m} < 1)$ can be quite well approximated with the vacuum model $(n_{m} = 1)$.

  11. Hall Effect in a Plasma.

    Science.gov (United States)

    Kunkel, W. B.

    1981-01-01

    Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

  12. Plasma focusing in coaxial gun

    International Nuclear Information System (INIS)

    A capacitor bank has been discharged between two coaxial electrodes of 6.6 cm outer diameter, 3.2 cm inner diameter and length of 31.5 cm. filled with hydrogen gas at pressure of 310 μHg. Results show that, the axial and radial plasma current reach a maximum value at a position adjacent to the gun muzzle, at which the plasma focus occurs. The measurement of the electron temperature and density and azimuthal electric field along the axis of the expansion chamber, gives a maximum value at z∼18 cm from the gun muzzle, while the axial plasma current and velocity has a minimum value at that position. These results indicate that a second point of a plasma focus has been formed at z∼18 cm from the gun muzzle, along the axis of the expansion chamber

  13. Coherent control of plasma dynamics

    CERN Document Server

    He, Z -H; Lebailly, V; Nees, J A; Krushelnick, K; Thomas, A G R

    2015-01-01

    Coherent control of a system involves steering an interaction to a final coherent state by controlling the phase of an applied field. Plasmas support coherent wave structures that can be generated by intense laser fields. Here, we demonstrate the coherent control of plasma dynamics in a laser wakefield electron acceleration experiment. A genetic algorithm is implemented using a deformable mirror with the electron beam signal as feedback, which allows a heuristic search for the optimal wavefront under laser-plasma conditions that is not known a priori. We are able to improve both the electron beam charge and angular distribution by an order of magnitude. These improvements do not simply correlate with having the `best' focal spot, since the highest quality vacuum focal spot produces a greatly inferior electron beam, but instead correspond to the particular laser phase that steers the plasma wave to a final state with optimal accelerating fields.

  14. Fueling by coaxial plasma guns

    International Nuclear Information System (INIS)

    The operating principles of pulsed coaxial guns are reviewed. Some problems involved with the injection of plasma beams from these guns into containment fields are described. The injection during reactor operating conditions is then discussed

  15. LDA measurements under plasma conditions

    International Nuclear Information System (INIS)

    A study was made of the application of Laser Doppler Anemometry (LDA) for the measurement of the fluid and particle velocities under plasma conditions. The flow configuration, is that of a dc plasma jet called the principal jet, in which an alumina powder of a mean particle diameter of 115 μm and a standard deviation of 11.3 μm was injected using a secondary jet. The plasma jet immerged from a 7.1 mm ID nozzle while that of the secondary jet was 2 nm in diameter. The secondary jet was introduced at the nozzle level of the plasma jet directed 900 to its axis. Details of the nozzle and the gas flow system are shown in Figure 2

  16. Plasma reactor waste management systems

    Science.gov (United States)

    Ness, Robert O., Jr.; Rindt, John R.; Ness, Sumitra R.

    1992-01-01

    The University of North Dakota is developing a plasma reactor system for use in closed-loop processing that includes biological, materials, manufacturing, and waste processing. Direct-current, high-frequency, or microwave discharges will be used to produce plasmas for the treatment of materials. The plasma reactors offer several advantages over other systems, including low operating temperatures, low operating pressures, mechanical simplicity, and relatively safe operation. Human fecal material, sunflowers, oats, soybeans, and plastic were oxidized in a batch plasma reactor. Over 98 percent of the organic material was converted to gaseous products. The solids were then analyzed and a large amount of water and acid-soluble materials were detected. These materials could possibly be used as nutrients for biological systems.

  17. Radioimmunoassay of human plasma trypsin

    International Nuclear Information System (INIS)

    A radioimmunoassay has been developed for the determination of human trypsin in plasma. It allows the measurement of trypsin concentration in spite of the presence of plasma or pancreatic inhibitors. The human trypsin used as a standard as well as for labelling was isolated from pancreatic tissue and purified by affinity chromatography. The antiserum was obtained from guinea-pigs immunized with partially purified human trypsin. In the radioimmunoassay, the values of trypsin in serial dilutions of plasma were parallel to those of the standard curves. The assay was shown to be reproducible, sensitive and specific. However, the two antisera used did not distinguish between the enzyme and its proenzyme. In normal subjects, plasma values were found to be around 400 ng/ml. They were 10-40 times higher in patients with acute pancreatitis. The method appears to be much more specific for the diagnosis of acute pancreatitis than the current determinations of amylase and lipase activity

  18. Tandem mirror plasma confinement apparatus

    International Nuclear Information System (INIS)

    Apparatus and method are described for confining a plasma in a center mirror cell by use of two end mirror cells as positively charged end stoppers to minimize leakage of positive particles from the ends of the center mirror cell

  19. LDA measurements under plasma conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lesinski, J.; Mizera-Lesinska, B.; Fanton, J.C.; Boulos, M.I.

    1979-01-01

    A study was made of the application of Laser Doppler Anemometry (LDA) for the measurement of the fluid and particle velocities under plasma conditions. The flow configuration, is that of a dc plasma jet called the principal jet, in which an alumina powder of a mean particle diameter of 115 ..mu..m and a standard deviation of 11.3 ..mu..m was injected using a secondary jet. The plasma jet immerged from a 7.1 mm ID nozzle while that of the secondary jet was 2 nm in diameter. The secondary jet was introduced at the nozzle level of the plasma jet directed 90/sup 0/ to its axis. Details of the nozzle and the gas flow system are shown in Figure 2.

  20. Plasma in the Heliosheath (Invited)

    Science.gov (United States)

    Richardson, J. D.

    2013-12-01

    The Voyager 2 plasma experiment has directly measured the heliosheath plasma since the termination shock crossing in 2007. This paper presents the data obtained up to December 2013. The flow direction has turned about 55 degrees in the RT plane, so some data are lost because of the angular response of the instrument. However, the plasma properties in the heliosheath fluctuate rapidly which allows much data to be recovered despite the high flow angles. The recent data show a continued slowing in the plasma speed and a turning tailward, with flow angles much larger in the RT than RN planes. The density increased in 2011 and has remained high; the flux has recovered to near the level observed at 1 AU. The temperature has remained near 50,000 K. These observations will be compared to V1 and model results.

  1. Compendium of laser plasma interaction

    International Nuclear Information System (INIS)

    Basic mechanisms, linear and non linear, are reviewed. Absorption through inverse Bremsstrahlung, through wave-wave couplings; resonant absorption; wave breaking; ponderomotive force; harmonic generation; magnetic field generation. Subsequent plasma flows are described

  2. The Wisconsin Plasma Astrophysics Laboratory

    CERN Document Server

    Forest, C B; Brookhart, M; Cooper, C M; Clark, M; Desangles, V; Egedal, J; Endrizzi, D; Miesch, M; Khalzov, I V; Li, H; Milhone, J; Nornberg, M; Olson, J; Peterson, E; Roesler, F; Schekochihin, A; Schmitz, O; Siller, R; Spitkovsky, A; Stemo, A; Wallace, J; Weisberg, D; Zweibel, E

    2015-01-01

    The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries which mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a 10 m$^3$, fully ionized, magnetic-field free plasma in a spherical geometry. Plasma parameters of $ T_{e}\\approx5-20$ eV and $n_{e}\\approx10^{11}-5\\times10^{12}$ cm$^{-3}$ provide an ideal testbed for a range of astrophysical experiments including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds, and more. This article describes the capabilities of WiPAL along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.

  3. Vircator operation at plasma assistance

    International Nuclear Information System (INIS)

    The influence of plasma on the processes of virtual cathode (VC) formation, high frequency (HF) generation, and plasma ions acceleration were studied. The theoretical consideration of the problem was analytically undertaken in one-dimensional approximation, that has shown the principal ability of low frequency (LF) oscillations of VC potential well and ion flow due to the periodic space charge neutralization by plasma ions. The experiments were carried out at the pulsed electron accelerator 'AGAT', which is a microsecond diode with a magnetic insulation. The accelerator produced an annular relativistic electron beam (REB). Plasma was produced by the beam electrons. It was observed that relaxing VC with low frequency modulation of 20 MHz was formed. The current of REB was temporary modulated at this frequency. The temporal modulation of intense REB is now proposed for excitation of slow space charge wave when further REB is being spatially modulated by periodic magnetic field. It constructs the scheme of the collective ion accelerator

  4. Fundamental studies of fusion plasmas

    International Nuclear Information System (INIS)

    This report discusses: ICRF impurity studies; ICRF convective cells; sheath plasma waves and anomalous IBW loading; a quasilinear description for fast wave minority heating permitting off magnetic axis heating in a tokamak; and runaway electrons studies in support of TEXT

  5. Plasma transport near material boundaries

    Energy Technology Data Exchange (ETDEWEB)

    Singer, C.E.

    1985-06-01

    The fluid theory of two-dimensional (2-d) plasma transport in axisymmetric devices is reviewed. The forces which produce flow across the magnetic field in a collisional plasma are described. These flows may lead to up-down asymmetries in the poloidal rotation and radial fluxes. Emphasis is placed on understanding the conditions under which the known 2-d plasma fluid equations provide a valid description of these processes. Attempts to extend the fluid treatment to less collisional, turbulent plasmas are discussed. A reduction to the 1-d fluid equations used in many computer simulations is possible when sources or boundary conditions provide a large enough radial scale length. The complete 1-d fluid equations are given in the text, and 2-d fluid equations are given in the Appendix.

  6. Plasma transport near material boundaries

    International Nuclear Information System (INIS)

    The fluid theory of two-dimensional (2-d) plasma transport in axisymmetric devices is reviewed. The forces which produce flow across the magnetic field in a collisional plasma are described. These flows may lead to up-down asymmetries in the poloidal rotation and radial fluxes. Emphasis is placed on understanding the conditions under which the known 2-d plasma fluid equations provide a valid description of these processes. Attempts to extend the fluid treatment to less collisional, turbulent plasmas are discussed. A reduction to the 1-d fluid equations used in many computer simulations is possible when sources or boundary conditions provide a large enough radial scale length. The complete 1-d fluid equations are given in the text, and 2-d fluid equations are given in the Appendix

  7. Dusty-Plasma Particle Accelerator

    Science.gov (United States)

    Foster, John E.

    2005-01-01

    A dusty-plasma apparatus is being investigated as means of accelerating nanometer- and micrometer-sized particles. Applications for the dusty-plasma particle accelerators fall into two classes: Simulation of a variety of rapidly moving dust particles and micrometeoroids in outer-space environments that include micrometeoroid streams, comet tails, planetary rings, and nebulae and Deposition or implantation of nanoparticles on substrates for diverse industrial purposes that could include hardening, increasing thermal insulation, altering optical properties, and/or increasing permittivities of substrate materials. Relative to prior apparatuses used for similar applications, dusty-plasma particle accelerators offer such potential advantages as smaller size, lower cost, less complexity, and increased particle flux densities. A dusty-plasma particle accelerator exploits the fact that an isolated particle immersed in plasma acquires a net electric charge that depends on the relative mobilities of electrons and ions. Typically, a particle that is immersed in a low-temperature, partially ionized gas, wherein the average kinetic energy of electrons exceeds that of ions, causes the particle to become negatively charged. The particle can then be accelerated by applying an appropriate electric field. A dusty-plasma particle accelerator (see figure) includes a plasma source such as a radio-frequency induction discharge apparatus containing (1) a shallow cup with a biasable electrode to hold the particles to be accelerated and (2) a holder for the substrate on which the particles are to impinge. Depending on the specific design, a pair of electrostatic-acceleration grids between the substrate and discharge plasma can be used to both collimate and further accelerate particles exiting the particle holder. Once exposed to the discharge plasma, the particles in the cup quickly acquire a negative charge. Application of a negative voltage pulse to the biasable electrode results in the

  8. Conditional Eddies in Plasma Turbulence

    DEFF Research Database (Denmark)

    Johnsen, H.; Pécseli, H.L.; Trulsen, J.

    1987-01-01

    Low‐frequency electrostatic turbulence generated by the ion–ion beam instability was investigated experimentally in a double‐plasma device. Real time signals were recorded and examined by a conditional statistical analysis. Conditionally averaged potential distributions reveal the formation and...... propagation of structures with a relatively long lifetime. Various methods for making a conditional analysis are discussed and compared. The results are discussed with reference to ion phase space vortices and clump formation in collisionless plasmas....

  9. Fusion Plasma Theory project summaries

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program.

  10. Breathing Modes in Dusty Plasma

    Institute of Scientific and Technical Information of China (English)

    王晓钢; 王爽; 潘秋惠; 刘悦; 贺明峰

    2003-01-01

    Acoustic breathing modes of dusty plasmas have been investigated in a cylindricalsystem with an axial symmetry. The linear wave solution and a "dispersion" relation were derived.It was found that in an infinite area, the mode is reduced to a "classical" dust acoustic wave inthe region away from the center. If the dusty plasma is confined in a finite region, however, thebreathing (or heart-beating) behavior would be found as observed in many experiments.

  11. PLASMA GASIFICATION OF WASTE PLASTICS

    OpenAIRE

    Tadeusz Mączka; Ewa Śliwka; Mateusz Wnukowski

    2013-01-01

    The article presents the process of obtaining liquid fuels and fuel gas in the process of plasma processing of organic materials, including waste plastics. The concept of plasma pyrolysis of plastics was presented and on its basis a prototype installation was developed. The article describes a general rule of operating the installation and its elements in the process and basic operation parameters determined during its start-up. Initial results of processing plastics and the directions furthe...

  12. Simulation science for fusion plasmas

    OpenAIRE

    Sudo, S.; Skoric, M.M.; Watanabe, T-H.; Todo, Y.; Ishizawa, A.; Miura, H; Ito, A; Ohtani, H.; Usami, S.; Nakamura, H; ITO, Atsushi; Ishiguro, S.; Tomita, Y.; Takayama, A.; M. Sato

    2008-01-01

    The world fusion effort has embarked into a new age with the construction of ITER in Cadarache, France, which will be the first magnetic confinement fusion plasma experiment dominated by the self-heating of fusion reactions. In order to operate and control burning plasmas and next generation demo fusion reactors, an advanced capability for comprehensive integrated computer simulations that are fully verified and validated against experimental data will be necessary. The ultimate goal is to pr...

  13. Simplifying plasma chemistry via ILDM

    Science.gov (United States)

    Rehman, T.; Kemaneci, E.; Graef, W.; van Dijk, J.

    2016-02-01

    A plasma fluid model containing a large number of chemical species and reactions yields a high computational load. One of the methods to overcome this difficulty is to apply Chemical Reduction Techniques as used in combustion engineering. The chemical reduction technique that we study here is ILDM (Intrinsic Lower Dimensional Manifold). The ILDM method is used to simplify an argon plasma model and then a comparison is made with a CRM (Collisional Radiative Model).

  14. Plasma Stability in Closed Systems

    International Nuclear Information System (INIS)

    The authors investigate the stability of closed plasma configurations using the general geometric criterion of local stability developed by Mercier and co-workers. To render in an explicit form the equilibrium configuration parameters on which the stability of the configuration depends, the general geometric criterion is transformed by expanding with respect to the deviation from the magnetic axis. In the resulting criterion the terms describing the ballooning mode and plasma stabilization through deepening of the magnetic well due to the toroidal magnetic surface displacement associated with the plasma pressure are rendered explicitly. For circular magnetic surface cross-sections these terms cancel out exactly and the stability condition is found to be independent of the plasma pressure. In the case of elliptical magnetic surface cross-sections, the effect of the ballooning instability predominates over deepening of the magnetic well. In this case the plasma pressure, which is critical for stability, is limited. The resulting stability criterion is applied to a number of toroidal systems. The authors consider the conditions for stability in closed systems with a spatial magnetic axis and in systems with a circular magnetic axis of the two-turn and three-turn stellarator type. They also consider the effect of the longitudinal current on plasma stability in such systems. In closed magnetic traps without longitudinal current, plasma stabilization is relatively simple in the presence of a shallow magnetic well. The critical value of β = 2p/B22 may exceed the relative depth of the vacuum magnetic well ΦV''/V' by an order of magnitude. When there is a longitudinal current, there appear additional factors that affect the stable containment of the plasma. (author)

  15. Entropy relaxation of ASDEX plasmas

    International Nuclear Information System (INIS)

    In tokamak discharges with improved ohmic confinement (IOC) in ASDEX a transition is observed from flat density profiles towards more peaked ones, while the normalized temperature profile is preserved. For this behaviour of the radial profiles it is shown that the entropy of the plasma increases during the IOC phase. Hence IOC and entropy relaxation are closely related. If the IOC phase is long enough, one finds stationary plasma states, which are compared with the relaxed state described in theory. (orig.)

  16. Cholecystokinin elevates mouse plasma lipids.

    Directory of Open Access Journals (Sweden)

    Lichun Zhou

    Full Text Available Cholecystokinin (CCK is a peptide hormone that induces bile release into the intestinal lumen which in turn aids in fat digestion and absorption in the intestine. While excretion of bile acids and cholesterol into the feces eliminates cholesterol from the body, this report examined the effect of CCK on increasing plasma cholesterol and triglycerides in mice. Our data demonstrated that intravenous injection of [Thr28, Nle31]-CCK at a dose of 50 ng/kg significantly increased plasma triglyceride and cholesterol levels by 22 and 31%, respectively, in fasting low-density lipoprotein receptor knockout (LDLR(-/- mice. The same dose of [Thr28, Nle31]-CCK induced 6 and 13% increases in plasma triglyceride and cholesterol, respectively, in wild-type mice. However, these particular before and after CCK treatment values did not achieve statistical significance. Oral feeding of olive oil further elevated plasma triglycerides, but did not alter plasma cholesterol levels in CCK-treated mice. The increased plasma cholesterol in CCK-treated mice was distributed in very-low, low and high density lipoproteins (VLDL, LDL and HDL with less of an increase in HDL. Correspondingly, the plasma apolipoprotein (apo B48, B100, apoE and apoAI levels were significantly higher in the CCK-treated mice than in untreated control mice. Ligation of the bile duct, blocking CCK receptors with proglumide or inhibition of Niemann-Pick C1 Like 1 transporter with ezetimibe reduced the hypercholesterolemic effect of [Thr28, Nle31]-CCK in LDLR(-/- mice. These findings suggest that CCK-increased plasma cholesterol and triglycerides as a result of the reabsorption of biliary lipids from the intestine.

  17. Fusion Plasma Theory project summaries

    International Nuclear Information System (INIS)

    This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program

  18. NONLINEAR ION STOPPING IN PLASMA

    OpenAIRE

    Avilov, S.; Meyer-ter-Vehn, J.; Peter, Th.

    1988-01-01

    We present an exact nonlinear solution of the one-dimensional Coulomb-Vlasov equations describing the stopping power of ions moving through a plasma. The solution is compared with the results of the corresponding linearized equations which are commonly used. We discuss the genuinely nonlinear regime. Nonlinear effects become important for highly charged ions at relatively low velocity. For heavy ion stopping in plasma they are relevant close to the end of the range. The method and the results...

  19. Plasma treatment advantages for textiles

    OpenAIRE

    Sparavigna, Amelia

    2008-01-01

    The textile industry is searching for innovative production techniques to improve the product quality, as well as society requires new finishing techniques working in environmental respect. Plasma surface treatments show distinct advantages, because they are able to modify the surface properties of inert materials, sometimes with environment friendly devices. For fabrics, cold plasma treatments require the development of reliable and large systems. Such systems are now existing and the use of...

  20. Mars Orbiting Plasma Surveyor (MOPS)

    OpenAIRE

    Barabash, Stas; André, Mats; Blomberg, Lars; Lundin, Rickard; Marklund, Göran; Rathsman, Peter; von Schéele, Fredrik; Wahlund, Jan-Erik

    2006-01-01

    Mars Orbiting Plasma Surveyor (MOPS) is a microsatellite mission focused on studies of the near -Mars environment and the planet - solar wind interaction. The recent findings by the ESA Mars Express mission further highlighted the complexity of the processes taking place at the planet resulting from the solar wind interaction that strongly affect the planet's atmosphere. However, despite many previous Martian missions carrying different types of space plasma experiments, a comprehensive inves...

  1. STUDY ON THE PRESSURE IN PLASMA ARC

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The axial pressure in plasma arc is measured under different conditions. The effects of the parameters, such as welding current, plasma gas flow rate, electrode setback and arc length, on the pressure in plasma arc are investigated and quantitative analyzed to explain the relationship between the quality of weld and the matching of parameters in plasma arc welding process.

  2. 21 CFR 640.60 - Source Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Source Plasma. 640.60 Section 640.60 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.60 Source Plasma. The proper name of the product shall be Source Plasma. The product is defined as the fluid portion of human...

  3. 21 CFR 640.30 - Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Plasma. 640.30 Section 640.30 Food and Drugs FOOD... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma § 640.30 Plasma. (a) Proper name and definition. The proper name of this component is Plasma. The component is defined as: (1) The fluid portion of one...

  4. 21 CFR 866.2160 - Coagulase plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Coagulase plasma. 866.2160 Section 866.2160 Food... DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2160 Coagulase plasma. (a) Identification. Coagulase plasma is a device that consists of freeze-dried animal or human plasma that...

  5. Zakharov equations in quantum dusty plasmas

    International Nuclear Information System (INIS)

    By generalizing the formalism of modulational interactions in quantum dusty plasmas, we derive the kinetic quantum Zakharov equations in dusty plasmas that describe nonlinear coupling of high frequency Langmuir waves to low frequency plasma density variations, for cases of non-degenerate and degenerate plasma electrons

  6. Electric Probe Diagnostic Supersonic Thermal Plasma Jet

    Czech Academy of Sciences Publication Activity Database

    Hurba, Oleksiy; Hrabovský, Milan

    Prague: Czech Technical University in Prague, Faculty of Electrical Engineering, 2014. s. 95. [SPPT 2014 - 26th Symposium on Plasma Physics and Technology/26./. 16.06.2014-19.06.2014, Prague] Keywords : thermal plasma * plasma spraying Subject RIV: BL - Plasma and Gas Discharge Physics

  7. Zakharov equations in quantum dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, F. [Center for Risk Management and Safety Sciences, Yokohama National University, Yokohama 240-8501 (Japan); Vladimirov, S. V. [Center for Risk Management and Safety Sciences, Yokohama National University, Yokohama 240-8501 (Japan); Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya st. 13 Bld. 2, Moscow 125412 (Russian Federation); Metamaterials Laboratory, National Research University of Information Technology, Mechanics, and Optics, St. Petersburg 199034 (Russian Federation); Ishihara, O. [Center for Risk Management and Safety Sciences, Yokohama National University, Yokohama 240-8501 (Japan); Institute of Science and Technology Research, Chubu University, Kasugai 487-8501 (Japan)

    2015-08-15

    By generalizing the formalism of modulational interactions in quantum dusty plasmas, we derive the kinetic quantum Zakharov equations in dusty plasmas that describe nonlinear coupling of high frequency Langmuir waves to low frequency plasma density variations, for cases of non-degenerate and degenerate plasma electrons.

  8. Treatment of Waste Materials in Thermal Plasma

    Czech Academy of Sciences Publication Activity Database

    Hrabovský, Milan

    Kiev: -, 2006, s. 187. [International Congress on Plasma Physics/13th./. Kiev (UA), 22.05.2006-26.05.2006] R&D Projects: GA ČR GA202/05/0669 Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma pyrolysis * thermal plasma * syngas * biomass Subject RIV: BL - Plasma and Gas Discharge Physics

  9. Analysis and design of plasma monopole antenna

    OpenAIRE

    Wei, Li; Jinghui, Qiu; Ying, Suo

    2009-01-01

    Two kinds of plasma monopole antennas are simulated and analyzed in this article. For different radius, reflection coefficient, radiation pattern and radiation efficiency of a cylindrical plasma monopole antenna are calculated respectively. According to actual situation, a conical plasma monopole antenna with different cone angle is simulated. Impedance and radiation characteristics of the plasma antenna are similar to the metal monopole antenna.

  10. Progress report : Plasma Physics Section

    International Nuclear Information System (INIS)

    The activities of the plasma physics section of the Bhabha Atomic Research Centre, India over the last five years (1970-75) are reported. The R and D programme of the section has been divided into four cells mainly i.e., (i) Thermal plasma (ii) Relativistic Electron Beam (iii) Energetics and (iv) Electron beam technology. The salient features of the development activities carried out in these cells are outlined. In the Thermal plasma group, considerable research work has been done in (a) fundamental plasma studies, (b) industrial plasma technology and (c) open cycle MHD power generation project. The relativistic electron beam group is engaged in improving the technology to realize high power lasers, and pulsed thermonuclear fusion. The energetics programme is oriented to develop high voltage d.c. generators and pulse generators. The electron beam techniques developed here are routinely used for melting refractory and reactive metals. The technical know-how of the welding machines developed has been transfered to industries. Equipment developed by this section, such as, (1) electron beam furnace, (2) plasma cutting torch, (3) impulse magnet charger etc. are listed. (A.K.)

  11. Plasma chemistry in wire chambers

    International Nuclear Information System (INIS)

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an 55Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed

  12. ITER Plasma Control System Development

    Science.gov (United States)

    Snipes, Joseph; ITER PCS Design Team

    2015-11-01

    The development of the ITER Plasma Control System (PCS) continues with the preliminary design phase for 1st plasma and early plasma operation in H/He up to Ip = 15 MA in L-mode. The design is being developed through a contract between the ITER Organization and a consortium of plasma control experts from EU and US fusion laboratories, which is expected to be completed in time for a design review at the end of 2016. This design phase concentrates on breakdown including early ECH power and magnetic control of the poloidal field null, plasma current, shape, and position. Basic kinetic control of the heating (ECH, ICH, NBI) and fueling systems is also included. Disruption prediction, mitigation, and maintaining stable operation are also included because of the high magnetic and kinetic stored energy present already for early plasma operation. Support functions for error field topology and equilibrium reconstruction are also required. All of the control functions also must be integrated into an architecture that will be capable of the required complexity of all ITER scenarios. A database is also being developed to collect and manage PCS functional requirements from operational scenarios that were defined in the Conceptual Design with links to proposed event handling strategies and control algorithms for initial basic control functions. A brief status of the PCS development will be presented together with a proposed schedule for design phases up to DT operation.

  13. The Archimedes Plasma Mass Filter

    Science.gov (United States)

    Miller, R. L.; Ohkawa, T.; Agnew, S. F.; Cluggish, B. P.; Freeman, R. L.; Gilleland, J.; Putvinski, S.; Sevier, L.; Umstadter, K. R.

    2001-10-01

    Archimedes Technology Group is developing a plasma technology, called the Archimedes Plasma Mass Filter, which can separate a waste mixture ion by ion into mass groups and as such represents a major advance in waste separations technology. The filter is a plasma device employing a magnetic and electric field configuration that acts as a low-mass-pass filter for ions. Ions with mass above a tunable “cutoff mass” are expelled from the plasma. The Archimedes Plasma Mass Filter satisfies all of the requirements of an economic mass separator system: good single-pass separation, acceptable energy cost per ion, and high material throughput. This technology could significantly reduce the volume of radioactive waste at the Hanford Site in Richland, Washington, which is storing sixty percent of the nation’s defense nuclear waste. The potential waste reduction is dramatic because 82 wtpresently scheduled to be vitrified (immobilized and stored in glass) at Hanford are below mass number 60 while 99.9the radioactivity comes from atoms above mass number 89. We will present the plasma physics basis for the filter effect, the fundamental parameter constraints, and modeling results of filter operation.

  14. EDITORIAL: Focus on Plasma Medicine

    Science.gov (United States)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  15. Antimicrobial outcomes in plasma medicine

    Science.gov (United States)

    Ryan, Thomas P.; Stalder, Kenneth R.; Woloszko, Jean

    2015-03-01

    Plasma is referred to as the fourth state of matter and is frequently generated in the environment of a strong electric field. The result consists of highly reactive species--ions, electrons, reactive atoms and molecules, and UV radiation. Plasma Medicine unites a number of fields, including Physics, Plasma Chemistry, Cell Biology, Biochemistry, and Medicine. The treatment modality utilizes Cold Atmospheric Plasma (CAP), which is able to sterilize and treat microbes in a nonthermal manner. These gas-based plasma systems operate at close to room temperature and atmospheric pressure, making them very practical for a range of potential treatments and are highly portable for clinical use throughout the health care system. The hypothesis is that gas based plasma kills bacteria, fungus, and viruses but spares mammalian cells. This paper will review systematic work which shows examples of systems and performance in regards to antimicrobial effects and the sparing of mammalian cells. The mechanism of action will be discussed, as well as dosing for the treatment of microbial targets, including sterilization processes, another important healthcare need. In addition, commercial systems will be overviewed and compared, along with evidence-based, patient results. The range of treatments cover wound treatment and biofilms, as well as antimicrobial treatment, with little chance for resistance and tolerance, as in drug regimens. Current clinical studies include applications in dentistry, food treatment, cancer treatment, wound treatment for bacteria and biofilms, and systems to combat health care related infections.

  16. Argon plasma irradiation of polypropylene

    International Nuclear Information System (INIS)

    Polypropylene samples were exposed to argon plasma discharge and the changes of the PP surface properties were studied by different methods. Surface wettability was derived from contact angle measured by standard goniometry and chemical structure of the plasma modified PP was studied using X-ray photoelectron spectroscopy (XPS) and by Rutherford backscattering spectroscopy (RBS), surface morphology and roughness of samples using AFM. Zeta potential of pristine and modified PP was determined with the SurPASS. The presence of incorporated oxygen in the PP surface layer, about 60 nm thick, was observed in RBS spectra. Oxygen concentration is a decreasing function of the depth. With progressing aging time the oxygen concentration on the PP surface decreases. Plasma treatment results in a rapid decrease of the contact angle, which increases again with increasing aging time. In XPS measurement the oxygen containing structures, created by the plasma treatment, were found on the very surface of the modified PP and the zeta potential being changed too. The significant difference in zeta potential between pristine and plasma treated PP clearly indicates that the plasma treatment leads to a more hydrophilic PP surface.

  17. Plasma physics via particle simulation

    International Nuclear Information System (INIS)

    Plasmas are studied by following the motion of many particles in applied and self fields, analytically, experimentally and computationally. Plasmas for magnetic fusion energy devices are very hot, nearly collisionless and magnetized, with scale lengths of many ion gyroradii and Debye lengths. The analytic studies of such plasmas are very difficult as the plasma is nonuniform, anisotropic and nonlinear. The experimental studies have become very expensive in time and money, as the size, density and temperature approach fusion reactor values. Computational studies using many particles and/or fluids have complemented both theories and experiments for many years and have progressed to fully three dimensional electromagnetic models, albeit with hours of running times on the fastest largest computers. Particle simulation methods are presented in some detail, showing particle advance from acceleration to velocity to position, followed by calculation of the fields from charge and current densities and then further particle advance, and so on. Limitations due to the time stepping and use of a spatial grid are given, to avoid inaccuracies and instabilities. Examples are given for an electrostatic program in one dimension of an orbit averaging program, and for a three dimensional electromagnetic program. Applications of particle simulations of plasmas in magnetic and inertial fusion devices continue to grow, as well as to plasmas and beams in peripheral devices, such as sources, accelerators, and converters. (orig.)

  18. Atomic physics in tokamak plasmas

    International Nuclear Information System (INIS)

    Tokamak discharges produce hydrogen-isotope plasmas in a quasi-steady state, with radial electron temperature, Tsub(e)(r), and density nsub(e)(r), distribution usually centrally peaked, with typical values Tsub(e)(0) approx.= 1 - 3 keV, nsub(e)(r) approx.= 1014 cm-3. Besides hydrogen, the plasma contains small quantities of carbon, oxygen, various construction or wall-conditioning materials such as Fe, Cr, Ni, Ti, Zr, Mo, and perhaps elements added for special diagnostic purposes, e.g., Si, Sc, Al, or noble gases. These elements are spatially fairly homogeneously distributed, with the different ionization states occurring near radial locations where Tsub(e)(r) approx.= Esub(i), the ionization potential. Thus, spectroscopic measurements of various plasma properties, such as ion temperatures, plasma motions or oscillations, radial transport rates, etc. are automatically endowed with spatial resolution. Furthermore the emitted spectra, even of heavier elements such as Fe or Ni, are fairly simple because only the ground levels are appreciably populated under the prevailing plasma conditions. Identification of near-ground transitions, including particularly magnetic dipole and intercombination transitions of ions with ionization potentials in the several keV range, and determination of their collisional and radiative transition probabilities will be required for development of appropriate diagnostics of tokamak-type plasma approaching the prospective fusion reactor conditions. (orig.)

  19. Spatial control of processing plasmas in a multicusp plasma source equipped with a movable magnetic filter

    OpenAIRE

    Fukumasa, Osamu; Naitou, Hiroshi; Sakiyama, Satoshi

    1991-01-01

    It is confirmed, with the use of both a movable magnetic filter and a plasma grid, that plasma parameters (H_2-CH_4 or Ar-CH_4 plasmas) are spatially well controlled. At any filter position, plasma parameters change steeply across the magnetic filter. Then, a plasma source is divided into two parts, i. e. a source plasma region (high density plasma with energetic electrons) and a diffused plasma region (low density and low temperature plasma without energetic electrons). The former is suitabl...

  20. On plasma ion beam formation in the Advanced Plasma Source

    International Nuclear Information System (INIS)

    The Advanced Plasma Source (APS) is employed for plasma ion-assisted deposition (PIAD) of optical coatings. The APS is a hot cathode dc glow discharge which emits a plasma ion beam to the deposition chamber at high vacuum (p ≲ 2 × 10−4 mbar). It is established as an industrial tool but to date no detailed information is available on plasma parameters in the process chamber. As a consequence, the details of the generation of the plasma ion beam and the reasons for variations of the properties of the deposited films are barely understood. In this paper the results obtained from Langmuir probe and retarding field energy analyzer diagnostics operated in the plasma plume of the APS are presented, where the source was operated with argon. With increasing distance to the source exit the electron density (ne) is found to drop by two orders of magnitude and the effective electron temperature (Te,eff) drops by a factor of five. The parameters close to the source region read ne ≳ 1011 cm−3 and Te,eff ≳ 10 eV. The electron distribution function exhibits a concave shape and can be described in the framework of the non-local approximation. It is revealed that an energetic ion population leaves the source region and a cold ion population in the plume is build up by charge exchange collisions with the background neutral gas. Based on the experimental data a scaling law for ion beam power is deduced, which links the control parameters of the source to the plasma parameters in the process chamber. (paper)

  1. The plasma position control of ITER EDA plasma

    Energy Technology Data Exchange (ETDEWEB)

    Senda, Ikuo; Nishio, Satoshi; Tsunematsu, Toshihide [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Nishino, Toru; Fujieda, Hirobumi

    1994-09-01

    The study on the plasma position control of ITER EDA performed by Japan Home Team during the sensitivity study in 1994 is summarized. The controllabilities of plasmas in the Outline Design and elongated version are compared. The model used to describe the motion of the plasma is a rigid model. The PD feedback control is applied with respect to the displacements of the plasma from the equilibrium. Three types of fluctuations, which initiate the motion of the plasma, are examined, namely a finite horizontal fluctuation field, a small horizontal fluctuation field such that the motion of the plasma is governed by the passive structures and an abrupt change of the poloidal beta {beta}{sub p} and internal inductance l{sub i}. In the simulations of finite horizontal fluctuation fields, controls depend on the strength of the fluctuations, for instance, 3-5V is needed for 5-10G of fluctuation fields in the Outline Design. When the fluctuation field is small and the plasma displacement grows in a characteristic time of the passive structures, a few volt of the control voltage is enough to obtain good controllability. It is shown that the control when ({beta}{sub p}, l{sub i}) changes simultaneously is demanding and a large control voltage is required to maintain satisfactory control. Comparing the elongated version with the Outline Design, the control voltage which is larger than the Outline Design by a factor of 2-3 is required to obtain the same controllability in the elongated version. (author).

  2. Selforganisation in Plasma Physics

    Science.gov (United States)

    Tendler, M.

    2004-01-01

    The bottom line of modern plasma physics addressing a many body problem is the lack of thermodynamic potentials for the system in which fluxes are no longer linear functions of forces or gradients. Indeed far from the classical equilibrium, a system can still converge to a stationary state, yet not defined by the proper thermodynamic potential in contrast to the entropy production principle valid only for a linear or weakly nonlinear system. In this case, we confront an important issue of stability of a strongly nonequilibrium system occurring and lacking the thermodynamic potential. In a linear system the equilibrium is defined by the minimum of the potential and therefore the stability of the resulting steady-state is easily found. Of course, any fluctuation causes a deviation from the equilibrium. Yet, linear or weakly nonlinear system will return to this steady state due to the second law of thermodynamics. Hence, the existence of the thermodynamic potential makes the equilibrium very robust. Given the potential, any evolution of a weakly nonlinear system will result in a static stationary state. In contrast, a strongly nonlinear system may loose a steady state very easily due to instability perturbed by fluctuations. If this is the case the fluctuation will be amplified until a very different steady state not described by a minimum of the thermodynamic potential emerges. In more detail, instability in a strongly nonlinear situation has always to exceed a given threshold in order to yield a different equilibrium far from an original static steady state. In fluids and plasmas it is well-known that any laminar motion can transform into a turbulent motion once a given fluid velocity is exceeded. It may appear that this transition yields a chaotic strongly fluctuating equilibrium. Indeed although at the macroscopic level this novel equilibrium may appear to be a complete disorder and chaos, it is found experimentally that at the microscopic level the new

  3. Some new trends in plasma physics

    International Nuclear Information System (INIS)

    In this article author describes some recent developments in different areas of plasma physics i.e. nuclear fusion, plasma processing of materials, dusty plasma and plasma crystals. Fusion energy remains an important energy source. Nuclear fusion needs very high ion temperature to provide the kinetic energy to overcome the coulomb barrier. Energetic plasma particles activate the surface by producing radicals on the surface which interact with plasma species. Dust plasmas are of importance in many areas of active research, although the presence of dust is in some cases a very important factor. As the the dust particle number density is increased, collective effects become increasingly important, and at some point conditions are reached, where the dust particles have to be regarded as one of the components of the plasma. Plasma crystal is the term used to describe the recently discovered ordered state than colloidal plasma may assume under certain condition. (A.B.)

  4. Megawatt Electromagnetic Plasma Propulsion

    Science.gov (United States)

    Gilland, James; Lapointe, Michael; Mikellides, Pavlos

    2003-01-01

    The NASA Glenn Research Center program in megawatt level electric propulsion is centered on electromagnetic acceleration of quasi-neutral plasmas. Specific concepts currently being examined are the Magnetoplasmadynamic (MPD) thruster and the Pulsed Inductive Thruster (PIT). In the case of the MPD thruster, a multifaceted approach of experiments, computational modeling, and systems-level models of self field MPD thrusters is underway. The MPD thruster experimental research consists of a 1-10 MWe, 2 ms pulse-forming-network, a vacuum chamber with two 32 diffusion pumps, and voltage, current, mass flow rate, and thrust stand diagnostics. Current focus is on obtaining repeatable thrust measurements of a Princeton Benchmark type self field thruster operating at 0.5-1 gls of argon. Operation with hydrogen is the ultimate goal to realize the increased efficiency anticipated using the lighter gas. Computational modeling is done using the MACH2 MHD code, which can include real gas effects for propellants of interest to MPD operation. The MACH2 code has been benchmarked against other MPD thruster data, and has been used to create a point design for a 3000 second specific impulse (Isp) MPD thruster. This design is awaiting testing in the experimental facility. For the PIT, a computational investigation using MACH2 has been initiated, with experiments awaiting further funding. Although the calculated results have been found to be sensitive to the initial ionization assumptions, recent results have agreed well with experimental data. Finally, a systems level self-field MPD thruster model has been developed that allows for a mission planner or system designer to input Isp and power level into the model equations and obtain values for efficiency, mass flow rate, and input current and voltage. This model emphasizes algebraic simplicity to allow its incorporation into larger trajectory or system optimization codes. The systems level approach will be extended to the pulsed inductive

  5. Radioimmunoassay of plasma corticotrophin

    International Nuclear Information System (INIS)

    An assay has been established, based on antibodies against the N-terminal part of the ACTH molecule with a high affinity, a detection limit of 2 pg ACTH when assaying 200 ul unextracted plasma, and implying a total incubation time of three days. The antibody has been obtained by immunizing guinea-pigs with synthetic human 1-24 ACTH coupled to bovine serum albumin. The selected antibody has an equilibrium constant of 4 x 1011 litres/mole in a final dilution of 1/320.000. The antiserum reacts with synthetic human 1-39 ACTH as well as with synthetic human 1-24 ACTH, and the hormonally inactive synthetic human 11-24 ACTH fragment as well as alpha- and beta-melanocyte-stimulating hormones do not cross-react in the assay. The interassay coefficient of variation of replicate estimates was 11-13%. The reproducibility of the standard curve have been evaluated by calculating the amount of ACTH corresponding to 5% of the (B/T)o value, 1.2+-0.4 pg ACTH/tube+-SD and 50% of (B/T)o value, 15.7+-2.6 pg ACTH/tube+-SD. Validation of the assay has been obtained by assaying samples from patients with verified adrenal disorders, and the accuracy is supported by ACTH determinations in test, where metyrapon had been administered intravenously. A stimulation of ACTH production by insulin-induced hypoglycaemia has been found as well. Special attention is always paid as to the conditions for the blood sampling. A reference interval of 10-76 ng/l has been found (115 normal subjects). (orig.)

  6. 2010 Winter Conference on Plasma Spectrochemistry

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ The 2010 Winter Conference on Plasma Spectrochemistry,sixteenth in a series of biennial meetings sponsored by the ICP Information Newsletter, features developments in plasma spectrochemical analysis by inductively coupled plasma (ICP), dc plasma (DCP), microwave plasma (MIP), glow discharge (GDL, HCL), and laser sources. The meeting will be held Monday, January 4 through Saturday, January 9, 2010, in Fort Myers, Florida (www. fortmyers-sanibel, corn) at the Sanibel Harbour Resort and Spa (www. sanibel-resort, com).

  7. Plasma beam discharge in carbon dioxide

    International Nuclear Information System (INIS)

    The paper deals with the dissociation of carbon dioxide in nonequilibrium plasma of a stationary plasma-beam discharge. Experimental results of spectroscopic and probe measurements of plasma parameters are given. Moreover, a mass-spectrometric analysis of gaseous products of the chemical reactions is presented. In addition the measurement of the deposition rate of solid products by means of a quartz oscillator is described. The results show that plasma beam discharge is an effective tool for inducing plasma-chemical reactions. (author)

  8. Two stream instabilities in degenerate quantum plasmas

    OpenAIRE

    Son, S.

    2013-01-01

    The quantum mechanical effect on the plasma two-stream instability is studied based on the dielectric function approach. The analysis suggests that the degenerate plasma relevant to the inertial confinement fusion behaves differently from classical plasmas when the electron drift velocity is comparable to the Fermi velocity. For high wave vector comparable to the Fermi wave vector, the degenerate quantum plasma has larger regime of the two-stream instabilities than the classical plasma. A reg...

  9. Low temperature plasma technology methods and applications

    CERN Document Server

    Chu, Paul K

    2013-01-01

    Written by a team of pioneering scientists from around the world, Low Temperature Plasma Technology: Methods and Applications brings together recent technological advances and research in the rapidly growing field of low temperature plasmas. The book provides a comprehensive overview of related phenomena such as plasma bullets, plasma penetration into biofilms, discharge-mode transition of atmospheric pressure plasmas, and self-organization of microdischarges. It describes relevant technology and diagnostics, including nanosecond pulsed discharge, cavity ringdown spectroscopy, and laser-induce

  10. A Short Introduction to Plasma Physics

    OpenAIRE

    Wiesemann, K.

    2014-01-01

    This chapter contains a short discussion of some fundamental plasma phenomena. In section 2 we introduce key plasma properties like quasi-neutrality, shielding, particle transport processes and sheath formation. In section 3 we describe the simplest plasma models: collective phenomena (drifts) deduced from single-particle trajectories and fundamentals of plasma fluid dynamics. The last section discusses wave phenomena in homogeneous, unbounded, cold plasma.

  11. Reduced energy conservation law for magnetized plasma

    International Nuclear Information System (INIS)

    A global energy conservation law for a magnetized plasma is studied within the context of a quasiparticle description. A reduced energy conservation law is derived for low-frequency, as compared to the gyromagnetic frequency, plasma motions with regard to both non-uniform mean flows and fluctuations in the plasma. The mean value of plasma energy is calculated and sufficient stability conditions for non-equilibrium plasmas are derived. (orig.)

  12. X-ray hot plasma diagnostics

    International Nuclear Information System (INIS)

    X-ray plasma emission study is powerful diagnostic tool of hot plasmas. In this review article the main techniques of X-ray plasma emission measurement are shortly presented: X-ray spectrometry using absorbent filters, crystal and grating spectrometers, imaging techniques using pinhole cameras, X-ray microscopes and Fresnel zone plate cameras, X-ray plasma emission calorimetry. Advances in these techniques with examples for different hot plasma devices are also presentes. (author)

  13. Therapeutic Non Thermal Plasma, Significance and Challenges

    OpenAIRE

    Wameath Sh. Abdul-Majeed

    2014-01-01

    Plasma is an electrically neutral, highly ionized gas that consists of several species (electrons, ions, reactive species, and UV light) and classified into localized thermal equilibrium (LTE) plasmas and non-localized thermal equilibrium (n-LTE) plasmas. In LTE plasmas, the electron temperature exists in equilibrium with the gas temperature. In contrast, the electron temperature in (n- LTE) plasmas can reach temperatures of 1-10 (eV) while the gas temperature is kept as low as room temperatu...

  14. Plasma waves in parametric interactions

    Science.gov (United States)

    Yampolsky, Nikolai Andreevich

    The nonlinear laser-plasma interaction is widely discussed in the modern plasma literature with applications to inertial confinement fusion, generation of fast electrons, and amplification of high power radiation. Among nonlinear wave phenomena in plasma, the parametric wave coupling often plays the dominant role in laser-plasma interaction at moderate laser intensities since it is the lowest order nonlinear effect. The plasma wave can mediate the parametric laser coupling with high efficiency. We study the interplay of the parametric laser-plasma interaction and other physical effects which may affect this interaction. We study this interplay with an emphasis on the plasma-based backward Raman amplifier (BRA) based on the three-wave coupling. Three major types of physical effects in the parametric wave coupling are studied. In the first part of the thesis, we find the longitudinal profiles of the interacting waves in cases of interest for pulse compression. We find the solution for the output pulse in backward Raman amplification seeded by a laser pulse of finite duration. We also propose a new scheme for high-power amplification for pulses in the terahertz frequency range. For this scheme, based on the four-wave mixing in a capillary filled with plasma, we find the profile of the output pulse. The second part of this thesis is devoted to transverse effects, which may reduce the focusability of the output pulse in backward Raman amplification. We find that the transverse modulations of the pump can be averaged and do not reduce the amplified pulse focusability if the longitudinal length of these modulations is much smaller than the amplification length. In the third part, we study the kinetic effects. We propose a simplified fluid model for the nonlinear Landau damping of a parametrically driven plasma wave and study the effect of nonlinear Landau damping in backward Raman amplification. This simplified model can be useful not only for understanding complex

  15. Plasma production for electron acceleration by resonant plasma wave

    Science.gov (United States)

    Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Croia, M.; Curcio, A.; Di Giovenale, D.; Di Pirro, G. P.; Filippi, F.; Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R.; Romeo, S.; Ferrario, M.

    2016-09-01

    Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10-100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10-100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC_LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

  16. Ion Beam Plasma Interactions in the ASTRAL Helicon Plasma Source.

    Science.gov (United States)

    Boivin, R. F.; Kesterson, A.; Kamar, O.; Lin, Y.; Munoz, J.; Wang, X.

    2008-11-01

    A 100 KeV NEC duoplasmatron is used to produce an energetic ion beam (10 KeV ASTRAL helicon plasma source. The beam current and beam size are measured by a device combining Retarding Field Analyzer (RFA) and Faraday Cup (FC) features. ASTRAL produces bright intense He/Ne/Ar plasmas with the following parameters: ne = 1E11 -- 1E13 cm-3 and Te = 2 - 10 eV, B-field < 1.3 kGauss, rf power <= 2 kWatt. RF compensated Langmuir probes are used to measure Te and ne. Depending on the ion beam energy and the ratio of beam density over plasma density different wave instabilities will be generated within the plasmas. A real-time spectrum analyzer will be used to identify the wave instabilities and their evolution in the plasma. We will present early experimental results together with some preliminary theoretical simulation using 2D and 3D hybrid simulation codes. In these codes, ions are treated as fully kinetic particles while electrons are treated as a fluid. Both species are moving in a self-consistent electromagnetic field.

  17. ECR Plasma Sterilisation, Argon and Nitrogen Treated Plasma

    Science.gov (United States)

    Helhel, Selcuk; Oksuz, Lutfi; Cerezci, Osman; Rad, Abbas Y.

    2004-09-01

    ECR type plasma system was built to produce plasma in axial direction. Plasma was initiated in a specially designed Nickel - Chrome cylindrical vacuum tube which is being driven through dielectric window by 2.45GHz commercial magnetron source. Tube is also surrounded by a coil driving 150ADC to generate approximately 875Gauss magnetic field at the center. Langmuir probe and ICCD for optical spectrometry were used to characterize internal parameters like electron density, electron temperature and different characteristics of the plasma. Bacillus Subtilis var nigar, bacillus Stearothermophilus, bacillus pumilus E601, Escherichia coli and staphylococcus aureus type bacteria were selected as a reference. Each is resistant for different actions while the Bacilus cereus is the most resistant bacteria for microwave interaction. This study presents the effect of system on used bacteria. Those are gram positive and gram negative bacteria that refers to structure of cell wall. The sterilization efficacy of Argon type ECR plasma was found to be over 99, 5% in Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis (vegetative cell), Bacillus cereus (vegetative cell), Bacillus pumilus and Escherichia coli. System response type is less than 2 minutes.

  18. Experimental studies of collisional plasma shocks and plasma interpenetration via merging supersonic plasma jets

    Science.gov (United States)

    Hsu, S. C.; Moser, A. L.; Merritt, E. C.; Adams, C. S.

    2015-11-01

    Over the past 4 years on the Plasma Liner Experiment (PLX) at LANL, we have studied obliquely and head-on-merging supersonic plasma jets of an argon/impurity or hydrogen/impurity mixture. The jets are formed/launched by pulsed-power-driven railguns. In successive experimental campaigns, we characterized the (a) evolution of plasma parameters of a single plasma jet as it propagated up to ~ 1 m away from the railgun nozzle, (b) density profiles and 2D morphology of the stagnation layer and oblique shocks that formed between obliquely merging jets, and (c) collisionless interpenetration transitioning to collisional stagnation between head-on-merging jets. Key plasma diagnostics included a fast-framing CCD camera, an 8-chord visible interferometer, a survey spectrometer, and a photodiode array. This talk summarizes the primary results mentioned above, and highlights analyses of inferred post-shock temperatures based on observations of density gradients that we attribute to shock-layer thickness. We also briefly describe more recent PLX experiments on Rayleigh-Taylor-instability evolution with magnetic and viscous effects, and potential future collisionless shock experiments enabled by low-impurity, higher-velocity plasma jets formed by contoured-gap coaxial guns. Supported by DOE Fusion Energy Sciences and LANL LDRD.

  19. Wakes in Inertial Fusion Plasmas

    Science.gov (United States)

    Ellis, Ian Norman

    Plasma wave wakes, which are the collective oscillatory response near the plasma frequency to the propagation of particles or electromagnetic waves through a plasma, play a critical role in many plasma processes. New results from backwards stimulated Raman scattering (BSRS), in which wakes with phase velocities much less than the speed of light are induced by the beating of counter-propagating light waves, and from electron beam stopping, in which the wakes are produced by the motion of relativistically propagating electrons through the dense plasma, are discussed. Both processes play important roles in Inertial Confinement Fusion (ICF). In BSRS, laser light is scattered backwards out of the plasma, decreasing the energy available to compress the ICF capsule and affecting the symmetry of where the laser energy hits the hohlraum wall in indirect drive ICF. The plasma wave wake can also generate superthermal electrons that can preheat the core and/or the ablator. Electron beam stopping plays a critical role in the Fast Ignition (FI) ICF concept, in which a beam of relativistic electrons is used to heat the target core to ignition temperatures after the compression stage. The beam stopping power determines the effectiveness of the heating process. This dissertation covers new discoveries on the importance of plasma wave wakes in both BSRS and electron beam stopping. In the SRS studies, 1D particle-in-cell (PIC) simulations using OSIRIS are performed, which model a short-duration (˜500/ω0 --1FWHM) counter-propagating scattered light seed pulse in the presence of a constant pump laser with an intensity far below the absolute instability threshold for plasma waves undergoing Landau damping. The seed undergoes linear convective Raman amplification and dominates over the amplification of fluctuations due to particle discreteness. The simulation results are in good agreement with results from a coupled-mode solver when special relativity and the effects of finite size PIC

  20. Extreme hydrogen plasma densities achieved in a linear plasma generator

    International Nuclear Information System (INIS)

    A magnetized hydrogen plasma beam was generated with a cascaded arc, expanding in a vacuum vessel at an axial magnetic field of up to 1.6 T. Its characteristics were measured at a distance of 4 cm from the nozzle: up to a 2 cm beam diameter, 7.5x1020 m-3 electron density, ∼2 eV electron and ion temperatures, and 3.5 km/s axial plasma velocity. This gives a 2.6x1024 H+ m-2 s-1 peak ion flux density, which is unprecedented in linear plasma generators. The high efficiency of the source is obtained by the combined action of the magnetic field and an optimized nozzle geometry. This is interpreted as a cross-field return current that leads to power dissipation in the beam just outside the source

  1. Survey of Galileo plasma observations in Jupiter's plasma sheet

    Science.gov (United States)

    Bagenal, Fran; Wilson, Robert J.; Siler, Scott; Paterson, William R.; Kurth, William S.

    2016-05-01

    The plasma science (PLS) instrument on the Galileo spacecraft (orbiting Jupiter from December 1995 to September 2003) measured properties of the ions that were trapped in the magnetic field. The PLS data provide a survey of the plasma properties between ~5 and 30 Jupiter radii (RJ) in the equatorial region. We present plasma properties derived via two analysis methods: numerical moments and forward modeling. We find that the density decreases with radial distance by nearly 5 orders of magnitude from ~2 to 3000 cm-3 at 6 RJ to ~0.05 cm-3 at 30 RJ. The density profile did not show major changes from orbit to orbit, suggesting that the plasma production and transport remained constant within about a factor of 2. The radial profile of ion temperature increased with distance which implied that contrary to the concept of adiabatic cooling on expansion, the plasma heats up as it expands out from Io's orbit (where Ti ~ 60-80 eV) at ~6 RJ to a few keV at 30 RJ. There does not seem to be a long-term, systematic variation in ion temperature with either local time or longitude. This latter finding differs from earlier analysis of Galileo PLS data from a selection of orbits. Further examination of all data from all Galileo orbits suggests that System III variations are transitory on timescales of weeks, consistent with the modeling of Cassini Ultraviolet Imaging Spectrograph observations. The plasma flow is dominated by azimuthal flow that is between 80% and 100% of corotation out to 25 RJ.

  2. Simulation of burning tokamak plasmas

    International Nuclear Information System (INIS)

    To simulate dynamical behaviour of tokamak fusion reactors, a zero-dimensional time-dependent particle and power balance code has been developed. The zero-dimensional plasma model is based on particle and power balance equations that have been integrated over the plasma volume using prescribed profiles for plasma parameters. Therefore, the zero-dimensional model describes the global dynamics of a fusion reactor. The zero-dimensional model has been applied to study reactor start-up, and plasma responses to changes in the plasma confinement, fuelling rate, and impurity concentration, as well as to study burn control via fuelling modulation. Predictions from the zero-dimensional code have been compared with experimental data and with transport calculations of a higher dimensionality. In all cases, a good agreement was found. The advantage of the zero-dimensional code, as compared to higher-dimensional transport codes, is the possibility to quickly scan the interdependencies between reactor parameters. (88 refs., 58 figs., 6 tabs.)

  3. [Plasma properties research: Task 3

    International Nuclear Information System (INIS)

    The principal research activities of the Magneto-Fluid Dynamics Division relate to magnetic fusion plasma physics. In addition, there is a modest amount of work in closely related areas, including space plasma physics, fluid dynamics, and dynamical systems. Members of the Magneto-Fluid Dynamics Division maintain close contacts with fusion researchers in the US and abroad. Some of the work of the Division is clearly directed towards ITER and TPX, while other problems relate to the broader development of fusion plasma physics and to the support of other issues arising in the many experimental programs. Topics of some note in the last year that are discussed in this report are: Application of sophisticated statistical techniques to tokamak data reduction, including time series analysis of TFTR fluctuation data and spline analysis of profile data. Continuing development of edge plasma and divertor modelling, including initial ergodic divertor studies. Analysis of energetic fusion products losses from TFTR plasmas. Examination of anomalous transport in dynamical systems induced by chaotic-like Hamiltonian motion. Numerical simulation of the development of singular MHD equilibria. Exploration of the validity of moment expansions of kinetic equations for weakly collisional systems. Studies of RF- and ripple-induced helium ash removal. Ballooning mode studies in fluids and rotating stars. Studies in dynamical systems, including explosive instabilities, development of chaos, and motion of collisionless particles in a domain with overlapping islands

  4. Photoaffinity Labeling of Plasma Proteins

    Directory of Open Access Journals (Sweden)

    Masaki Otagiri

    2013-11-01

    Full Text Available Photoaffinity labeling is a powerful technique for identifying a target protein. A high degree of labeling specificity can be achieved with this method in comparison to chemical labeling. Human serum albumin (HSA and α1-acid glycoprotein (AGP are two plasma proteins that bind a variety of endogenous and exogenous substances. The ligand binding mechanism of these two proteins is complex. Fatty acids, which are known to be transported in plasma by HSA, cause conformational changes and participate in allosteric ligand binding to HSA. HSA undergoes an N-B transition, a conformational change at alkaline pH, that has been reported to result in increased ligand binding. Attempts have been made to investigate the impact of fatty acids and the N-B transition on ligand binding in HSA using ketoprofen and flunitrazepam as photolabeling agents. Meanwhile, plasma AGP is a mixture of genetic variants of the protein. The photolabeling of AGP with flunitrazepam has been utilized to shed light on the topology of the protein ligand binding site. Furthermore, a review of photoaffinity labeling performed on other major plasma proteins will also be discussed. Using a photoreactive natural ligand as a photolabeling agent to identify target protein in the plasma would reduce non-specific labeling.

  5. High Z laser plasma experiments

    International Nuclear Information System (INIS)

    Understanding the coupling of high powered lasers to dense plasmas is a first step toward the realization of laser driven fusion. At LLNL there is a continuing effort to understand the coupling of short wavelength lasers to high Z plasmas. The intensity and wavelength dependence of absorption, energy partition and instability thresholds have been studied in order to develop a good predictive capability for high Z laser-produced plasmas. These studies, begun on Argus, Shiva and Novette, and most recently continued on the Nova laser facility, have extended the wavelength scaling studies from 1.06 to 0.26 μm wavelength using frequency multiplication techniques to convert the fundamental 1.06 μm wavelength of our Nd-glass lasers to shorter wavelengths. In general, shorter wavelength light couples more efficiently to the plasma with absorption measured as greater than 80% for 0.53 μm wavelength and 90% for 0.35 μm wavelength at intensities up to 10/sup 15/ W/cm/sup 2/. For high Z plasmas significant laser energy is converted to low energy x rays. In this paper, the author gives a brief overview of Nova, the present experimental facility, and its diagnostic capability. The author then presents highlights of the experiments and present understanding of high Z interaction experiments

  6. Plasma Processing of Advanced Materials

    Energy Technology Data Exchange (ETDEWEB)

    Heberlein, Joachim, V.R.; Pfender, Emil; Kortshagen, Uwe

    2005-02-28

    Plasma Processing of Advanced Materials The project had the overall objective of improving our understanding of the influences of process parameters on the properties of advanced superhard materials. The focus was on high rate deposition processes using thermal plasmas and atmospheric pressure glow discharges, and the emphasis on superhard materials was chosen because of the potential impact of such materials on industrial energy use and on the environment. In addition, the development of suitable diagnostic techniques was pursued. The project was divided into four tasks: (1) Deposition of superhard boron containing films using a supersonic plasma jet reactor (SPJR), and the characterization of the deposition process. (2) Deposition of superhard nanocomposite films in the silicon-nitrogen-carbon system using the triple torch plasma reactor (TTPR), and the characterization of the deposition process. (3) Deposition of films consisting of carbon nanotubes using an atmospheric pressure glow discharge reactor. (4) Adapting the Thomson scattering method for characterization of atmospheric pressure non-uniform plasmas with steep spatial gradients and temporal fluctuations. This report summarizes the results.

  7. Microwave diagnostics of atmospheric plasmas

    Science.gov (United States)

    Scott, David

    Plasma treatment of biological tissues has tremendous potential due to the wide range of applications. Most plasmas have gas temperatures which greatly exceed room temperature. These are often utilized in electro-surgery for cutting and coagulating tissue. Another type of plasma, referred to as cold atmospheric plasma, or CAP, is characterized by heavy particle temperatures which are at or near room temperature. Due to this lack of thermal effect, CAP may provide less invasive medical procedures. Additionally, CAP have been demonstrated to be effective at targeting cancer cells while minimizing damage to the surrounding tissue. A recently fabricated Microwave Electron Density Device (MEDD) utilizes microwave scattering on small atmospheric plasmas to determine the electron plasma density. The MEDD can be utilized on plasmas which range from a fraction of a millimeter to several centimeters at atmospheric pressure when traditional methods cannot be applied. Microwave interferometry fails due to the small size of the plasma relative to the microwave wavelength which leads to diffraction and negligible phase change; electrostatic probes introduce very strong perturbation and are associated with difficulties of application in strongly-collisional atmospheric conditions; and laser Thomson scattering is not sensitive enough to measure plasma densities less than 1012 cm-3. The first part of this dissertation provides an overview of two types of small atmospheric plasma objects namely CAPs and plasmas utilized in the electro-surgery. It then goes on to describe the fabrication, testing and calibration of the MEDD facility. The second part of this dissertation is focused on the application of the MEDD and other diagnostic techniques to both plasma objects. A series of plasma images that illustrate the temporal evolution of a discharge created by an argon electrosurgical device operating in the coagulation mode and its behavior was analyzed. The discharge of the argon

  8. EDITORIAL: Focus on Plasma Medicine

    Science.gov (United States)

    Morfill, G. E.; Kong, M. G.; Zimmermann, J. L.

    2009-11-01

    'Plasma Healthcare' is an emerging interdisciplinary research topic of rapidly growing importance, exploring considerable opportunities at the interface of plasma physics, chemistry and engineering with life sciences. Some of the scientific discoveries reported so far have already demonstrated clear benefits for healthcare in areas of medicine, food safety, environmental hygiene, and cosmetics. Examples include ongoing studies of prion inactivation, chronic wound treatment and plasma-mediated cancer therapy. Current research ranges from basic physical processes, plasma chemical design, to the interaction of plasmas with (i) eukaryotic (mammalian) cells; (ii) prokaryotic (bacteria) cells, viruses, spores and fungi; (iii) DNA, lipids, proteins and cell membranes; and (iv) living human, animal and plant tissues in the presence of biofluids. Of diverse interests in this new field is the need for hospital disinfection, in particular with respect to the alarming increase in bacterial resistance to antibiotics, the concomitant needs in private practices, nursing homes etc, the applications in personal hygiene—and the enticing possibility to 'design' plasmas as possible pharmaceutical products, employing ionic as well as molecular agents for medical treatment. The 'delivery' of the reactive plasma agents occurs at the gaseous level, which means that there is no need for a carrier medium and access to the treatment surface is optimal. This focus issue provides a close look at the current state of the art in Plasma Medicine with a number of forefront research articles as well as an introductory review. Focus on Plasma Medicine Contents Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination Helen C Baxter, Patricia R Richardson, Gaynor A Campbell, Valeri I Kovalev, Robert Maier, James S Barton, Anita C Jones, Greg DeLarge, Mark Casey and Robert L Baxter Inactivation factors of spore-forming bacteria using low

  9. Fundamental studies of fusion plasmas

    International Nuclear Information System (INIS)

    Work on ICRF interaction with the edge plasma is reported. ICRF generated convective cells have been established as an important mechanism for influencing edge transport and interaction with the H-mode, and for controlling profiles in the tokamak scrape-off-layer. Power dissipation by rf sheaths has been shown to be significant for some misaligned ICRF and IIBW antenna systems. Near-field antenna sheath work has been extended to the far-field case, important for experiments with low single pass absorption. Impurity modeling and Faraday screen design support has been provided for the ICRF community. In the area of core-ICRF physics, the kinetic theory of heating by applied ICRF waves has been extended to retain important geometrical effects relevant to modeling minority heated tokamak plasmas, thereby improving on the physics base that is standard in presently employed codes. Both the quasilinear theory of ion heating, and the plasma response function important in wave codes have been addressed. In separate studies, it has been shown that highly anisotropic minority heated plasmas can give rise to unstable field fluctuations in some situations. A completely separate series of studies have contributed to the understanding of tokamak confinement physics. Additionally, a diffraction formalism has been produced which will be used to access the focusability of lower hybrid, ECH, and gyrotron scattering antennas in dynamic plasma configurations

  10. Spectroscopic investigation of plasma turbulence

    International Nuclear Information System (INIS)

    Optical studies of plasma fluctuations have been carried out in a toroidal, high-voltage discharge: the Plasma Betatron experiment at the University of Saskatchewan. Following the formation of the helium plasma, of density 1019-1020m-3, by rf preionization and a preheating field, the electric field (1P-41D (4922 A) and 2/3P-43D (4471 A) lines show that low (ω<<ωsub(pe)) and high (ωapproximatelyωsub(pe)) frequency fluctuations are present at early times (t <2μs). The rms field strengths are comparable, at < approximately 2kV/cm. An analysis is given of the possible role of these fluctuations in the rapid thermal transport previously observed from the current skin layer to the interior of the plasma. Direct energy transport by propagating electron plasma or ion acoustic waves is shown to be insignificant. However, the low frequency field strength is sufficient to allow for an explanation in terms of enhanced thermal diffusion due to lower hybrid waves. (author)

  11. Weakly nonlinear electron plasma waves in collisional plasmas

    DEFF Research Database (Denmark)

    Pecseli, H. L.; Rasmussen, J. Juul; Tagare, S. G.;

    1986-01-01

    The nonlinear evolution of a high frequency plasma wave in a weakly magnetized, collisional plasma is considered. In addition to the ponderomotive-force-nonlinearity the nonlinearity due to the heating of the electrons is taken into account. A set of nonlinear equations including the effect...... of a constantly maintained pump wave is derived and a general dispersion relation describing the modulation of the high frequency wave due to different low frequency responses is obtained. Particular attention is devoted to a purely growing modulation. The relative importance of the ponderomotive force...

  12. Plasma Heating and Burnout in Beam-Plasma Interaction

    International Nuclear Information System (INIS)

    Experiments using beam-plasma interaction to generate fully ionized plasma and enhance the temperature of the components are in progress at Oak Ridge National Laboratory. Previous experimental work demonstrated that an electron beam of 5 keV could heat plasma electrons in a magnetic mirror machine to a temperature over 100 keV. In this extension of the earlier work the electron beam is directed through higher pressure gas. Such a dense cloud of electrons is produced that neutral gas streaming inward from the walls is almost completely ionized or burned out before reaching the center of the apparatus. The most spectacular feature of the burnout transition is the sudden decrease of spectral light by a factor about 1000. Several neutral beam transmission experiments give electron densities greater than 1012 cm-3. Microwave cut-off measurements agree with this lower limit. Direct measurements of the electron plasma frequency and the ion plasma frequency give a density of 5 x 1012 cm-3. Once the neutral gas in the plasma is ionized, the electron cooling by excitation processes and the ion cooling by charge-exchange phenomena disappear; therefore, any electron and ion heating caused by the electron beam should have time to take effect. Pin-hole camera images formed by 50-keV X-rays give evidence of electron heating. Ion heating is limited by wall proximity to 20-keV deuterons in the Burnout IV device and 200-keV deuterons in the larger Burnout V device. Magnetic and electrostatic analysis give evidence for the existence of some deuterons at 20 keV in Burnout IV; similar analysis is in progress on Burnout V. In Burnout V the electron beam traverses the central 300 cm3 of the 10-liter volume between the mirrors of a 40-20-40-kG mirror machine. Injection and multiple reflection of the 45-kW electron beam occur outside the mirrors in a region of 10-5 Torr ambient pressure. The lifetime of the plasma is difficult both to measure and to predict on theoretical grounds. The

  13. Plasma Limiter Based on Surface Wave Plasma Excited by Microwave

    Institute of Scientific and Technical Information of China (English)

    YANG Geng; TAN Jichun; SHEN Benjian

    2008-01-01

    A novel plasma limiter, in which the plasma is excited by surface wave, is presented. The breakdown time of some gases filled in the limiter were calculated as a function of gas pres-sure, ionization degree and density of seed electrons under low pressure (0.01 ~1 Torr) and high pressure (10 ~1000 Torr) cases. The results show that the limiter filled with Xe with a pressure of 0.9 Torr, seed electron density of 1016 m-3, and ionization degree of 10-4, has a breakdown time of approximate 19.6 ns.

  14. Plasma-based radar cross section reduction

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generatio...

  15. Confinement and heating of FRC plasma

    International Nuclear Information System (INIS)

    Confinement times of particle and trapped magnetic flux in FRC plasmas were simulated using a one dimensional transport modal and classical (Spitzer's) resistivity. Comparing the simulation results and experimental results indicated that a transport in the plasmas was basically classical and deviations of experimental results from classical values (so-called anomaly) might attribute to a plasma geometry effect, by which the deviation was larger for fat plasmas and smaller for prolate ones. In order to verify this indication, a plasma electron heating with an axial injection of pulsed and intense ion beams was proposed for the plasmas in current FRC experiments. Possibility of this heating were examined by estimating an energy deposit rate of a beam ion in the plasmas. The energy deposit rate is a few% to about 100% for a plasma of 12cm in diameter and 80cm in length with a plasma parameter range of current experiments. 6 refs., 7 figs., 1 tab

  16. Portable nanosecond pulsed air plasma jet

    International Nuclear Information System (INIS)

    Low-temperature atmospheric pressure plasmas are of great importance in many emerging biomedical and materials processing applications. The redundancy of a vacuum system opens the gateway for highly portable plasma systems, for which air ideally becomes the plasma-forming gas and remote plasma processing is preferred to ensure electrical safety. Typically, the gas temperature observed in air plasma greatly exceeds that suitable for the processing of thermally liable materials; a large plasma-sample distance offers a potential solution but suffers from a diluted downstream plasma chemistry. This Letter reports a highly portable air plasma jet system which delivers enhanced downstream chemistry without compromising the low temperature nature of the discharge, thus forming the basis of a powerful tool for emerging mobile plasma applications.

  17. Plasma control concepts for ITER

    International Nuclear Information System (INIS)

    This overview paper skims over a wide range of issues related to the control of ITER plasmas. Although operation of the ITER project will require extensive developmental work to achieve the degree of control required, there is no indication that any of the identified problems will present overwhelming difficulties compared with the operation of present tokamaks. However, the precision of control required and the degree of automation of the final ITER plasma control system will present a challenge which is somewhat greater than for present tokamaks. In order to operate ITER optimally, integrated use of a large amount of diagnostic information will be necessary, evaluated and interpreted automatically. This will challenge both the diagnostics themselves and their supporting interpretation codes. The intervening years will provide us with the opportunity to implement and evaluate most of the new features required for ITER on existing tokamaks, with the exception of the control of an ignited plasma. (author) 7 figs., 7 refs

  18. Plasma model of superconducting crystals

    Science.gov (United States)

    Netesova, Nadezhda P.

    2016-04-01

    Within inharmonious plasma oscillation model the superconducting crystal AB is considered consisting of two subsystems 2AB=A2+B2. In high-temperature superconductors spontaneous division into two phases: superconducting and isolating was revealed. Phase separation was caused by plasma instability. It is obtained the transition superconducting phase temperature dependence Tc = F (q12, q1, q2, V12, V1, V2) on the isotopic substitution physical parameters: q - initial and component interaction parameters, V - volume in initial and component crystal lattices. The isotopic transition superconducting phase temperature displacement ΔTc is associated with the change of the initial and component interaction and crystal lattice parameters. From the plasma mechanism of superconductivity follows superconducting crystals exist at room temperature.

  19. Plasma physics for controlled fusion

    CERN Document Server

    Miyamoto, Kenro

    2016-01-01

    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator includi...

  20. Alternative approaches to plasma confinement

    Science.gov (United States)

    Roth, J. R.

    1978-01-01

    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.