GRAVITATIONAL-INSTABILITY OF A THERMALLY CONDUCTING VISCOUS HALL PLASMA

The gravitational instability of an infinite homogeneous viscous thermally conducting plasma of finite electrical conductivity in the presence of Hall currents has been studied here. It is assumed that the plasma is permeated by a horizontal magnetic field. The dispersion relation has been obtained and solved numerically to obtain the dependence of the growth rate of gravitationally unstable modes on the various parameters involved. It is shown that Jeans' criterion remains unchanged in the presence of the effects of thermal conductivity, viscosity, rotation, magnetic resistivity and collisions. It is found that viscosity, collision with neutrals and thermal conductivity have stabilizing influence while magnetic resistivity has a destabilizing influence on the growth rate of the unstable mode of disturbance.