Propagation of waves in a gravitating and rotating anisotropic heat conducting plasma

  • Gebretsadkan W. B.
Keywords: Waves, Instabilities, Rotating, Drift, Gravitating, Anisotropy.

Abstract

An inviscid, unbounded, collisionless, gravitating, rotating and heat conducting anisotropic plasma medium which is drifting is considered. The medium is assumed to be embedded in a strong magnetic field. A general dispersion relation is derived using normal mode analysis and its various limiting cases are discussed, compared with similar earlier results for a non-drifting model, and some disagreements are indicated. The dispersion relation reveals the existence of five waves. These different wave modes are discussed in some particular cases analytically. It is found that in the case of parallel propagation all the five waves propagate. When the axis of rotation is across the magnetic field, the modified entropy wave and the modified anisotropic Alfven wave are independent of rotation, gravitation and heat flux. It is shown that the drift velocity has no effect on the stability of these waves but their phase velocities are found to be altered by the drift velocity; the forward propagating modes being increased and the backward modes decreased. The other three waves are affected by gravitation, rotation, drift and parallel component of the heat flux. It is further shown that only two waves propagate in the perpendicular direction. The propagating wave modes in this particular direction are not affected by the drift velocity since wave normal is transverse to the direction of flow.

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Published
2018-06-05