ON THE STABILITY OF A PARTIALLY IONIZED PLASMA

Year 2020, Volume: 1 Issue: 1, 41 - 49, 03.11.2020

Pardeep Kumar , Hari Mohan

Abstract

The Rayleigh-Taylor instability of an infinitely conducting plasma of variable density in the presence of a horizontal magnetic field is considered when the effects of finite ion Larmor radius (FLR) and collisions with neutral atoms simultaneously present. Here we considered the perturbations propagating along the ambient magnetic field. It is observed that, real part of n is negative, where n is the growth rate of disturbance, so that instability does not arise in the form of increasing amplitude, i.e. overstability. To obtain an approximate solution of the problem, a variational principle is used. The case of two semi-infinitely extending plasmas of constant densities separated by a horizontal interface is also considered, where it is found that the system is stable (for some wave numbers) for potentially stable configuration and unstable (for other wave numbers) for potentially unstable configuration even if there are collisions with dust particles. Also it is observed that the criteria determining stability and instability are independent of FLR effects.

Keywords

Rayleigh-Taylor instability, conducting plasma, horizontal magnetic field

Supporting Institution

NIL

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