TITLE

Quasi-thermal noise in space plasma: “kappa” distributions

AUTHOR(S)
Le Chat, G.; Issautier, K.; Meyer-Vernet, N.; Zouganelis, I.; Maksimovic, M.; Moncuquet, M.
PUB. DATE
October 2009
SOURCE
Physics of Plasmas;Oct2009, Vol. 16 Issue 10, p102903
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The transport of energy in collisionless plasmas, especially in space plasmas, is far from being understood. Measuring the temperature of the electrons and their nonthermal properties can give important clues to understand the transport properties. Quasi-thermal noise (QTN) spectroscopy is a reliable tool for measuring accurately the electron density and temperature since it is less sensitive to the spacecraft perturbations than particle detectors. This work models the plasma QTN using a generalized Lorentzian (“kappa”) distribution function for the electrons. This noise is produced by the quasi-thermal fluctuations of the electrons and by the Doppler-shifted thermal fluctuations of the ions. A sum of two Maxwellian functions has mainly been used for modeling the QTN of the electrons, but the observations have shown that the electrons are better fitted by a kappa distribution function. Pioneer work on QTN calculation only considered integer values of κ. This paper extends these calculations to real values of κ and gives the analytic expressions and numerical calculations of the QTN with a kappa distribution function. This paper shows some generic properties and gives some practical consequences for plasma wave measurements in space.
ACCESSION #
44910038

 

Related Articles

  • Hydromagnetic waves and instabilities in kappa distribution plasma. Basu, B. // Physics of Plasmas;May2009, Vol. 16 Issue 5, p052106 

    Stability properties of hydromagnetic waves (shear and compressional Alfven waves) in spatially homogeneous plasma are investigated when the equilibrium particle velocity distributions in both parallel and perpendicular directions (in reference to the ambient magnetic field) are modeled by kappa...

  • Conditions of the occurrence of charge instabilities in weakly ionized plasma flows. Perevoznikov, E. // Russian Physics Journal;Nov2004, Vol. 47 Issue 11, p1122 

    The dynamics of the perturbations of a weakly ionized plasma flow is considered in the context of three-fluid hydrodynamics. The conditions of the formation of flow-charge instabilities, which have been obtained in criterial form, are discussed.

  • Second Harmonic Generation in Plasma in the Presence of SBS. Khazanov, I.V. // JETP Letters;9/10/2003, Vol. 78 Issue 5, p285 

    The mechanism of second harmonic generation in the presence of intense-radiation SBS in plasma is considered under the condition that the incident beam has no time for filamentation. The mechanism is based on the formation of low-frequency plasma-density perturbations in the field of scattered...

  • ELM Dynamics in TCV H-modes. Degeling, A. W.; Martin, Y. R.; Lister, J. B.; Llobet, X.; Bak, P. E. // AIP Conference Proceedings;2003, Vol. 669 Issue 1, p223 

    TCV (Tokamak à Configuration Variable, R = 0.88 m, a < 0.25 m, B[SUBT] < 1.54 T) is a highly elongated tokamak, capable of producing limited and diverted plasmas, with the primary aim of investigating the effects of plasma shape and current profile on tokamak physics and performance. L-mode...

  • Equilibrium of non-neutral plasmas with weak axisymmetric magnetic perturbations. Romé, M.; Kotelnikov, I.; Kabantsev, A. // AIP Conference Proceedings;2006, Vol. 862 Issue 1, p116 

    The effect of weak external axisymmetric magnetic and electrostatic perturbations on the equilibrium of a non-neutral plasma confined in a Malmberg-Penning trap is analyzed. A semi-analytic solution for the potential variations inside the trap is found in a paraxial limit of the perturbations...

  • Anisotropic pressure, transport, and shielding of magnetic perturbations. Mynick, H. E.; Boozer, A. H. // Physics of Plasmas;Aug2008, Vol. 15 Issue 8, p082502 

    The effect on a tokamak of applying a nonaxisymmetric magnetic perturbation δB is computed. An equilibrium with scalar pressure p yields zero net radial current, and therefore zero torque. Thus, the usual approach, which assumes scalar pressure, is not self-consistent, and masks the close...

  • Stark Broadening of F III Lines in Laboratory and Stellar Plasma. Simić, Z.; Dimitrijević, M.; Popović, L. Č; Dačić, M. D. // Journal of Applied Spectroscopy;May2005, Vol. 72 Issue 3, p443 

    Using a semiclassical approach, we have considered electron-, proton-, and ionized helium-impact line widths and shifts for the F III 2p34So-3s 4P resonant line. Moreover, for 10 F III multiplets where the full semiclassical perturbation approach is not applicable in an adequate way due to the...

  • The internal waves and Rayleigh-Taylor instability in compressible quantum plasmas. Lu, H. L.; Qiu, X. M. // Physics of Plasmas;Oct2011, Vol. 18 Issue 10, p104508 

    In this paper, we investigate the quantum effect on internal waves and Rayleigh-Taylor (RT) instability in compressible quantum plasmas. First of all, let us consider the case of the limit of short wavelength perturbations. In the case, the dispersion relation including quantum and...

  • Rotation dependence of a phase delay between plasma edge electron density and temperature fields due to a fast rotating, resonant magnetic perturbation field. Stoschus, H.; Schmitz, O.; Frerichs, H.; Jakubowski, M. W.; Unterberg, B.; Abdullaev, S. S.; Clever, M.; Coenen, J. W.; Kruezi, U.; Schega, D.; Samm, U. // Physics of Plasmas;Jun2010, Vol. 17 Issue 6, p060702 

    Measurements of the plasma edge electron density ne and temperature Te fields during application of a fast rotating, resonant magnetic perturbation (RMP) field show a characteristic modulation of both, ne and Te coherent to the rotation frequency of the RMP field. A phase delay...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics