On Minimum-B Stabilization of Electrostatic Drift Instabilities
ثبت نشده
چکیده
A check is made of a stabilization theorem of ROSENBLUTH and KRALL (Phys. Fluids 8, 1004 [1965]) according to which an inhomogeneous plasma in a minimum-ß field {ß 1) should be stable with respect to electrostatic drift instabilities when the particle distribution functions satisfy a condition given by TAYLOR, i. e. when AND ^fl^W ] = 0 . A necessary and sufficient condition for stability is D (co = oo, k, .. .) k2 for all k, the dispersion relation being written in the form D (co, k, K, ...) =k2+K2. In the case fo)pi | Qi | adherence to the condition given by TAYLOR guarantees stability.
منابع مشابه
Instabilities in a thin current sheet and their consequences
Using a fully 3-D particle in-cell simulation, we studied the electrodynamics of a thin current sheet (CS). Starting with a uniform plasma and anti-parallel magnetic field, Harris equilibrium is achieved during the early stage of the simulation. In the processes of reaching the equilibrium, both electrons and ions in the newly formed CS are energized and develop pitch-angle anisotropies. We fin...
متن کاملResistive Instabilities in a Hall Thruster Under the Presence of Collisions and Thermal Motion of Electrons
The electrostatic and electromagnetic low frequency waves propagating in azimuthal direction in a Hall thruster channel are found to be unstable due to the resistive coupling to the electrons’ closed drift in the presence of collisions. The thermal motion of the electrons and their collisions significantly affect the growth of these waves. With respect to the collision frequency, wave number, e...
متن کاملElectrostatic Ion-Cyclotron Instabilities Modified by the Parallel and Perpendicular Plasma Flow Velocity Shears
The external and independent control of plasma flow velocity shears parallel and perpendicular to magnetic field lines is realized using segmented collisionless-plasma sources. Electrostatic ion-cyclotron instabilities are observed to be suppressed by the perpendicular flow velocity shears, the suppression physics of which is found to be distinguished into two aspects. On the other hand, the pa...
متن کاملElectrostatic waves and instabilities in multispecies nonneutral plasmas
This paper briefly describes waves and instabilities in a multispecies nonneutral plasma that have previously been studied only in neutral plasmas: ion sound waves, drift waves, and ion temperature gradient waves. The theory of their dispersion relations and growth rates is similar to that for neutral plasmas, but results differ in several important respects. For instance, drift waves are not n...
متن کاملParameter Drift Instability in Disturbance-Free Adaptive Systems
Adaptive identification and control algorithms can exhibit local instability when certain ideal assumptions, such as satisfaction of SPR conditions, are violated. However, recent conjectures suggest that due to a “self-stabilization” mechanism, global boundedness may still hold despite local instabilities. We present counterexamples to these conjectures, showing that self stabilization is bypas...
متن کامل