The Experts below are selected from a list of 15681 Experts worldwide ranked by ideXlab platform
Constantine E Theodosiou - One of the best experts on this subject based on the ideXlab platform.
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landau damping and anomalous skin effect in low pressure Gas Discharges self consistent treatment of collisionless heating
Physics of Plasmas, 2004Co-Authors: Igor D Kaganovich, Oleg Polomarov, Constantine E TheodosiouAbstract:In low-pressure Discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure Discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure Discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for t...
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landau damping and anomalous skin effect in low pressure Gas Discharges self consistent treatment of collisionless heating
Other Information: PBD: 30 Jan 2004, 2004Co-Authors: Igor D Kaganovich, Oleg Polomarov, Constantine E TheodosiouAbstract:In low-pressure Discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure Discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure Discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for the nonuniform plasma density profile for computing the current density profile and the EEDF is demonstrated. The enhancement of collisionless heating due to the bounce resonance between the electron motion in the potential well and the external radio-frequency electric field is investigated. It is shown that a nonlinear and self-consistent treatment is necessary for the correct description of collisionless heating.
Igor D Kaganovich - One of the best experts on this subject based on the ideXlab platform.
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landau damping and anomalous skin effect in low pressure Gas Discharges self consistent treatment of collisionless heating
Physics of Plasmas, 2004Co-Authors: Igor D Kaganovich, Oleg Polomarov, Constantine E TheodosiouAbstract:In low-pressure Discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure Discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure Discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for t...
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landau damping and anomalous skin effect in low pressure Gas Discharges self consistent treatment of collisionless heating
Other Information: PBD: 30 Jan 2004, 2004Co-Authors: Igor D Kaganovich, Oleg Polomarov, Constantine E TheodosiouAbstract:In low-pressure Discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure Discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure Discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for the nonuniform plasma density profile for computing the current density profile and the EEDF is demonstrated. The enhancement of collisionless heating due to the bounce resonance between the electron motion in the potential well and the external radio-frequency electric field is investigated. It is shown that a nonlinear and self-consistent treatment is necessary for the correct description of collisionless heating.
Vladimir Yegorenkov - One of the best experts on this subject based on the ideXlab platform.
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Validating the Goldstein-Wehner law for the stratified positive column of dc discharge in an undergraduate laboratory Validating the Goldstein-Wehner law for the stratified positive column of dc discharge in an undergraduate laboratory
2020Co-Authors: Valeriy Lisovskiy, E P Artushenko, V A Koval, Vladimir YegorenkovAbstract:Abstract In this paper we suggest a simple technique for validating the Goldstein-Wehner law for a stratified positive column of dc glow discharge while studying the properties of Gas Discharges in an undergraduate laboratory. To accomplish this a simple device with a pre-vacuum mechanical pump, dc source and Gas pressure gauge is required. Experiments may be performed in nitrogen or even in air. First you need to photograph the discharge tube with striations at different Gas pressure values and then you need to determine the thickness of the first striation on a computer monitor
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validating the goldstein wehner law for the stratified positive column of dc discharge in an undergraduate laboratory
European Journal of Physics, 2012Co-Authors: Valeriy Lisovskiy, Veronika Koval, E P Artushenko, Vladimir YegorenkovAbstract:In this paper we suggest a simple technique for validating the Goldstein–Wehner law for a stratified positive column of dc glow discharge while studying the properties of Gas Discharges in an undergraduate laboratory. To accomplish this a simple device with a pre-vacuum mechanical pump, dc source and Gas pressure gauge is required. Experiments may be performed in nitrogen or even in air. First you need to photograph the discharge tube with striations at different Gas pressure values and then you need to determine the thickness of the first striation on a computer monitor. (Some figures may appear in colour only in the online journal)
Zoltán Donkó - One of the best experts on this subject based on the ideXlab platform.
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first principles calculation of the effect of coulomb collisions in partially ionized Gases
Physics of Plasmas, 2014Co-Authors: Zoltán DonkóAbstract:Coulomb collisions, at appreciable ratios (η) of the electron to the neutral particle density, influence significantly the electron kinetics in particle swarms and in plasmas of Gas Discharges. This paper introduces a combination of Molecular Dynamics and Monte Carlo simulation techniques, to provide a novel, approximation-free, first principles calculation method for the velocity distribution function of electrons, and related swarm characteristics, at arbitrary η. Simulation results are presented for electrons in argon Gas, for density ratios between zero and 10−1, representing the limits of a negligible electron density and an almost complete Maxwellization of the velocity distribution function, respectively.
Ute Ebert - One of the best experts on this subject based on the ideXlab platform.
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proposing supercritical fluids as a replacement for sf 6 in high voltage power switches Gas Discharges in supercritical fluids for make and break operation
IEEE International Power Modulator and High Voltage Conference, 2016Co-Authors: E J M Van Heesch, Ute Ebert, W F L M Hoeben, F J C M Beckers, T Huiskamp, A J M Pemen, Aram Markosyan, Jin ZhangAbstract:Gas Discharges in supercritical fluids are an excellent candidate for high-power switching duty. Experimental and theoretical research has been performed. We present an analysis of results and a quick comparison with SF 6 and CO 2 .
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a time scale for electrical screening in pulsed Gas Discharges
Journal of Physics D, 2014Co-Authors: Jannis Teunissen, Anbang Sun, Ute EbertAbstract:The Maxwell time is a typical time scale for the screening of an electric field in a medium with a given conductivity. We introduce a generalization of the Maxwell time that is valid for Gas Discharges: the ionization screening time, that takes the growth of the conductivity due to impact ionization into account. We present an analytic estimate for this time scale, assuming a planar geometry, and evaluate its accuracy by comparing with one- and three-dimensional numerical simulations. We investigate the minimum plasma density required to prevent the growth of streamers with local field enhancement, and we discuss the effects of photoionization and electron detachment on ionization screening. Our results can help to understand the development of pulsed Discharges, for example nanosecond pulsed Discharges at atmospheric pressure or halo Discharges in the lower ionosphere.
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a time scale for electrical screening in pulsed Gas Discharges
arXiv: Plasma Physics, 2014Co-Authors: Jannis Teunissen, Anbang Sun, Ute EbertAbstract:The Maxwell time is a typical time scale for the screening of an electric field in a medium with a given conductivity. We introduce a generalization of the Maxwell time that is valid for Gas Discharges: the \emph{ionization screening time}, that takes the growth of the conductivity due to impact ionization into account. We present an analytic estimate for this time scale, assuming a planar geometry, and evaluate its accuracy by comparing with numerical simulations in 1D and 3D. We investigate the minimum plasma density required to prevent the growth of streamers with local field enhancement, and we discuss the effects of photoionization and electron detachment on ionization screening. Our results can help to understand the development of pulsed Discharges, for example nanosecond pulsed Discharges at atmospheric pressure or halo Discharges in the lower ionosphere.
