HR: 1330h
AN: SM43A-05 [Abstracts]
TI: Whistlers in the Inhomogeneous Plasma
AU: * Streltsov, A V
EM: streltsov@nrl.navy.mil
AF: Icarus Research Inc., 7113 Exfair Road, Bathesda, MD 20814 United States
AU: Lampe, M
AF: Plasma Physics Division
Naval Research Lab, 4555 Overlook Ave., SW, Washington, DC 20375 United States
AU: Manheimer, W M
AF: Icarus Research Inc., 7113 Exfair Road, Bathesda, MD 20814 United States
AU: Ganguli, G
AF: Plasma Physics Division
Naval Research Lab, 4555 Overlook Ave., SW, Washington, DC 20375 United States
AU: Joyce, G
AF: George Mason University, 4400 University Drive, Fairfax, VA 22030 United States
AB:
Results from a numerical study of the dynamics of the whistler waves in the magnetospheric plasma are presented. In this
study the plasma is considered to be homogeneous in the direction along
the ambient magnetic field and strongly inhomogeneous across it.
Thus the goal of this investigation is to understand the dynamics
of the whistlers inside the plasma chanel (duct) extended along
the ambient magnetic field and localized across it. The plasma
density inside the duct can be higher (high-density duct) or
lower (low-density duct) than the density outside the duct.
Analysis of the whistler dispersion relation predicts trapping of
the wave inside the duct depending on the parameters of the plasma,
ambient magnetic field, and the whistler itself (frequency, perpendicular
and parallel wavelength). But because this dispersion relation
is derived assuming the validity of the geometrical optic approximation,
it does not describe effects of the strong density gradients forming
the walls of the duct on the dynamics of the whistler. Numerical
simulations of the quasi-longitudinal, electron MHD model, providing
a full wave description of the whistler, reveal that these effects
can be quite important, particularly when the perpendicular
wavelength of the whistler is comparable to the scale-size of
the plasma inhomogeneity. In particular, simulations demonstrate
how the quality of the high-density duct depends on the scale-size
of the transverse inhomogeneity.
DE: 2730 Magnetosphere--inner
DE: 2753 Numerical modeling
DE: 2772 Plasma waves and instabilities
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly