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Didier Benisti - One of the best experts on this subject based on the ideXlab platform.

  • exact relativistic kinetic theory of the full unstable spectrum of an electron beam Plasma System with maxwell juttner distribution functions
    Physical Review E, 2010
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti
    Abstract:

    Following a recent Letter by Bret et al. [Phys. Rev. Lett. 100, 205008 (2008)], we present a detailed report of the entire unstable $\mathbf{k}$ spectrum of a relativistic collisionless beam-Plasma System within a fully kinetic framework. In contrast to a number of previously published studies, our linear analysis makes use of smooth momentum distribution functions of the Maxwell-J\"uttner form. The three competing classes of instabilities, namely, two-stream, filamentation, and oblique modes, are dealt with in a unified manner, no approximation being made regarding the beam-Plasma densities, temperatures, and drift energies. We investigate the hierarchy between the competing modes, paying particular attention to the relatively poorly known quasielectrostatic oblique modes in the regime where they govern the System. The properties of the fastest growing oblique modes are examined in terms of the System parameters and compared to those of the dominant two-stream and filamentation modes.

  • exact relativistic kinetic theory of an electron beam Plasma System hierarchy of the competing modes in the System parameter space
    Physical Review Letters, 2008
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti, E Lefebvre
    Abstract:

    The stability analysis of an electron-beam-Plasma System is of critical relevance in many areas of physics. Surprisingly, decades of extensive investigation have not yet resulted in a realistic unified picture of the multidimensional unstable spectrum within a fully relativistic and kinetic framework. All attempts made so far in this direction were indeed restricted to simplistic distribution functions and/or did not aim at a complete mapping of the beam-Plasma parameter space. The present Letter comprehensively tackles this problem by implementing an exact linear model. Three kinds of modes compete in the linear phase, which can be classified according to the direction of their wave number with respect to the beam. We determine their respective domain of preponderance in a three-dimensional parameter space and support our results with multidimensional particle-in-cell simulations.

Antoine Bret - One of the best experts on this subject based on the ideXlab platform.

  • exact relativistic kinetic theory of the full unstable spectrum of an electron beam Plasma System with maxwell juttner distribution functions
    Physical Review E, 2010
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti
    Abstract:

    Following a recent Letter by Bret et al. [Phys. Rev. Lett. 100, 205008 (2008)], we present a detailed report of the entire unstable $\mathbf{k}$ spectrum of a relativistic collisionless beam-Plasma System within a fully kinetic framework. In contrast to a number of previously published studies, our linear analysis makes use of smooth momentum distribution functions of the Maxwell-J\"uttner form. The three competing classes of instabilities, namely, two-stream, filamentation, and oblique modes, are dealt with in a unified manner, no approximation being made regarding the beam-Plasma densities, temperatures, and drift energies. We investigate the hierarchy between the competing modes, paying particular attention to the relatively poorly known quasielectrostatic oblique modes in the regime where they govern the System. The properties of the fastest growing oblique modes are examined in terms of the System parameters and compared to those of the dominant two-stream and filamentation modes.

  • exact relativistic kinetic theory of an electron beam Plasma System hierarchy of the competing modes in the System parameter space
    Physical Review Letters, 2008
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti, E Lefebvre
    Abstract:

    The stability analysis of an electron-beam-Plasma System is of critical relevance in many areas of physics. Surprisingly, decades of extensive investigation have not yet resulted in a realistic unified picture of the multidimensional unstable spectrum within a fully relativistic and kinetic framework. All attempts made so far in this direction were indeed restricted to simplistic distribution functions and/or did not aim at a complete mapping of the beam-Plasma parameter space. The present Letter comprehensively tackles this problem by implementing an exact linear model. Three kinds of modes compete in the linear phase, which can be classified according to the direction of their wave number with respect to the beam. We determine their respective domain of preponderance in a three-dimensional parameter space and support our results with multidimensional particle-in-cell simulations.

L Gremillet - One of the best experts on this subject based on the ideXlab platform.

  • exact relativistic kinetic theory of the full unstable spectrum of an electron beam Plasma System with maxwell juttner distribution functions
    Physical Review E, 2010
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti
    Abstract:

    Following a recent Letter by Bret et al. [Phys. Rev. Lett. 100, 205008 (2008)], we present a detailed report of the entire unstable $\mathbf{k}$ spectrum of a relativistic collisionless beam-Plasma System within a fully kinetic framework. In contrast to a number of previously published studies, our linear analysis makes use of smooth momentum distribution functions of the Maxwell-J\"uttner form. The three competing classes of instabilities, namely, two-stream, filamentation, and oblique modes, are dealt with in a unified manner, no approximation being made regarding the beam-Plasma densities, temperatures, and drift energies. We investigate the hierarchy between the competing modes, paying particular attention to the relatively poorly known quasielectrostatic oblique modes in the regime where they govern the System. The properties of the fastest growing oblique modes are examined in terms of the System parameters and compared to those of the dominant two-stream and filamentation modes.

  • exact relativistic kinetic theory of an electron beam Plasma System hierarchy of the competing modes in the System parameter space
    Physical Review Letters, 2008
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti, E Lefebvre
    Abstract:

    The stability analysis of an electron-beam-Plasma System is of critical relevance in many areas of physics. Surprisingly, decades of extensive investigation have not yet resulted in a realistic unified picture of the multidimensional unstable spectrum within a fully relativistic and kinetic framework. All attempts made so far in this direction were indeed restricted to simplistic distribution functions and/or did not aim at a complete mapping of the beam-Plasma parameter space. The present Letter comprehensively tackles this problem by implementing an exact linear model. Three kinds of modes compete in the linear phase, which can be classified according to the direction of their wave number with respect to the beam. We determine their respective domain of preponderance in a three-dimensional parameter space and support our results with multidimensional particle-in-cell simulations.

E Lefebvre - One of the best experts on this subject based on the ideXlab platform.

  • exact relativistic kinetic theory of an electron beam Plasma System hierarchy of the competing modes in the System parameter space
    Physical Review Letters, 2008
    Co-Authors: Antoine Bret, L Gremillet, Didier Benisti, E Lefebvre
    Abstract:

    The stability analysis of an electron-beam-Plasma System is of critical relevance in many areas of physics. Surprisingly, decades of extensive investigation have not yet resulted in a realistic unified picture of the multidimensional unstable spectrum within a fully relativistic and kinetic framework. All attempts made so far in this direction were indeed restricted to simplistic distribution functions and/or did not aim at a complete mapping of the beam-Plasma parameter space. The present Letter comprehensively tackles this problem by implementing an exact linear model. Three kinds of modes compete in the linear phase, which can be classified according to the direction of their wave number with respect to the beam. We determine their respective domain of preponderance in a three-dimensional parameter space and support our results with multidimensional particle-in-cell simulations.

Dong-wha Park - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Arc Discharge Mode on the Efficiency of Biogas Reforming in an AC-Pulsed Arc Plasma System
    Plasma Chemistry and Plasma Processing, 2017
    Co-Authors: Woo-jae Chung, Hyun-woo Park, Dong-wha Park
    Abstract:

    The effects of arc discharge mode on biogas reforming performance in an AC-pulsed arc Plasma System were investigated for different pulse rising times. The discharge mode changed from the re-strike arc mode to constant arc discharge mode on increasing the pulse rising time from 2 to 5 μs at a fixed discharge power. The length of the arc column periodically changed under re-strike mode, while the arc column was always longer under constant arc mode. The production yield of synthesis gas and the energy efficiency significantly improved when the arc discharge was operated under constant arc mode. The conversion rates of CH_4 and CO_2 increased from 15 to 80 and 12 to 27%, respectively. Under constant arc mode, the production yield of synthesis gas was 6.5 times higher than that under re-strike arc mode. In addition, the energy cost for synthesis gas production decreased remarkably from 52 to 9 kJ/mol. This is because the biogas reforming reactions, including thermal cracking, dry reforming, and partial oxidation, proceeded effectively in an area of the arc Plasma, wherein the gas could react in the high-enthalpy region for a duration sufficient to ensure efficient reforming reactions. Therefore, the arc discharge mode significantly affected the chemical reactions and energy efficiency of biogas reforming.

  • Synthesis of copper nanopowders by transferred arc and non-transferred arc Plasma Systems
    Journal of Optoelectronics and Advanced Materials, 2010
    Co-Authors: Mu-gap Shin, Dong-wha Park
    Abstract:

    Copper nanopowders were prepared from bulk material using a transferred arc Plasma System. N 2 diluting gas flow rate was introduced as an experimental parameter. It was observed that as the flow rate of the diluting gas was increased, the oxidation level of the copper nanopowders was greatly reduced and the particle size was also decreased. Also, copper nanopowders were prepared using a non-transferred arc Plasma System. The morphology and the particle size were changed by the flow rate of the N 2 added Plasma gas, as it was confirmed by the results of the scanning electron microscopy (SEM), particle size analyzer (PSA), X-ray diffractometer (XRD), transmission electron microscopy (TEM), elemental analyzer (EA), and thermogravimetric analyzer (TGA). The experimental results of the two types of the Plasma Systems showed the remarkable differences. The evaporation rate of the bulk copper by the transferred arc Plasma System was much higher than that of the non-transferred arc Plasma System. The mean particle size of the particles prepared by the transferred arc was 98 nm while that of the particles prepared by the non-transferred arc was about 202 nm confirmed by PSA.