Properties of Electromagnetic Waves in Plasmas

The stability of a charged surface of a magneto-radiative dusty plasma is investigated. It is shown that for a particular condition the surface can become unstable through two different mechanisms, one is when the surface is charged, while the other arises due to dissipation instabilities caused by the radiation energy flux. In the linear approximation, a general dispersion relation is derived, taking into account magneto -radiative effect, surface charge and gravity.The importance of thermal radiation on the Jeans instability is discussed for a magnetized dusty plasma with gravitaional effects. The one fluid MHD equations are developed by assuming that the entropy of each subsystem of plasma is conserved, when the temperature of plasma species is nonrelativistic. The dispersion relation, in this case shows that thermal radiation helps to stabilize Jeans instability. It is shown that the plasma is stable in certain range of wavelengths. The magnetic field stabilizes Jeans instability when the wave propagates across the magnetic field. However, for oblique propagation it is seen that the magnetic field does not stabilize Jeans instability.