Kinetic theory for electrostatic waves due to transverse velocity shears

Abstract

A kinetic theory in the form of an integral equation is provided to study the electrostatic oscillations in a collisionless plasma immersed in a uniform magnetic field and a nonuniform transverse electric field. In the low temperature limit (kyρi ≪1, where ky is the wave vector in the y direction and ρi is the ion gyroradius) the dispersion differential equation is recovered for the transverse Kelvin–Helmholtz modes for arbitrary values of k∥, where k∥ is the component of the wave vector in the direction of the external magnetic field assumed in the z direction. For higher temperatures (kyρi>1) the ion-cyclotron-like modes described earlier in the literature by Ganguli, Lee, and Palmadesso [Phys. Fluids 28, 761 (1985)] are recovered. In this article the integral equation is reduced to a second-order differential equation and a study is made of the kinetic Kelvin–Helmholtz and the ion-cyclotron-like modes that constitute the two branches of oscillation in a magnetized plasma including a transverse inhomogeneous dc electric field.

Laboratory simulation of broadband ELF waves in the auroral ionosphere

“…The IEDD instability mechanism, also capable of exciting current-driven electrostatic ion-cyclotron waves, is believed to be relevant to these energization processes as well [Gangull et al, 1985a]. A full kinetic analysis of the IEDD instability has been carried out [Ganguli et al, 1988b], and the existence of IEDD waves has been verified in the laboratory Amatucci et al, 1996]. On the basis of laboratory evidence and theoretical predictions, Bonnell [1997a] and Norqvist [1998] favor the IEDD instability over the CDEIC instability for the mechanism responsible for BB-ELF waves in the auroral ionosphere.…”

Inductive acceleration of UHECRs in sheared relativistic jets

“…As we show below [see also 34], in case of narrow shear layers, when Larmor radius becomes comparable to shear scale, particle motion becomes unstable even for homogeneous flow, without perturbing inertial Alfvén wave.…”

“…For low energy particles, with small but finite Larmor radii, variations of potential energy need to be taken into account for a correct description of the plasma distribution function in magnetized flows with transverse shear [34][35][36].…”

Laboratory Plasma Studies

“…an appg.im -formly as posslble. 40 In Connection With this point, Baresolution of the scalar wave equation at P is givais byUA kat's variational analysis of apodization problems in the context of Fraimhoier diffraction is noteworthy. 41 4r,0-…”