HR: 0800h
AN: SM51C-0674    [Abstracts]
TI: Linear Theory of Waves in Space Plasmas Modeled by Lorentzian (Kappa) Distribution
AU: * Basu, B
EM: Bamandas.Basu@hanscom.af.mil
AF: Air Force Research Laboratory, 29 Randolph Road, Hanscom AFB, MA 01731, United States
AB: Resonant wave-particle interaction plays an essential role in the growth or damping of many plasma waves in collisionless plasma. It also dominates the collective processes that produce anomalous transport of density, momentum and energy due to plasma turbulence. The resonant interaction involves particles that are moving with the speed of the plasma wave. Space plasmas, e.g., plasma in the Earth's magnetosphere and the solar wind, as well as astrophysical plasmas are characterized by particle distribution function, such as the Lorentzian (or kappa) distribution function, which has power-law energy dependence above the thermal energy. The presence of a substantially larger number of suprathermal particles in such a distribution, in contrast with a Maxwellian distribution, can significantly change the rate of growth or damping of plasma waves, as well as the rate of anomalous transport processes that rely on resonant wave-particle interaction. In this paper we present the linear theory of waves in current-carrying, inhomogeneous magnetoplasma in which the equilibrium state is modeled by the anisotropic kappa distribution function. The dispersion relation including the effects of the spatial gradients of density, temperature and flow velocity as well as those of the temperature anisotropy is derived. Such a comprehensive dispersion relation is useful for the study of the various plasma waves that can be excited in space plasma situation. The dispersion relation is used to obtain the excitation conditions and the growth rates of a few interesting plasma waves, and the results are compared and contrasted with those in Maxwellian plasma.
DE: 2471 Plasma waves and instabilities (2772)
DE: 2483 Wave/particle interactions (7867)
DE: 2772 Plasma waves and instabilities (2471)
DE: 7829 Kinetic waves and instabilities
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting