Effect of transport coefficients on the damping of hydromagnetic waves

Abstract

The general theory of the propagation of hydromagnetic waves in a magnetized plasma is presented taking into account the finite ion-Larmor radius, the electrical and thermal conductivities, and the thermoelectric coefficients of the plasma. The dispersion relation is obtained as the exact solution of the linearized macroscopic moment equations of the Boltzmann equation derived by Marshall. The dispersion relation is solved in the special cases when the wave propagation is along the static magnetic field or transverse to it. The damping coefficient of the waves is given. It is found that in the case of propagation along the field lines, the damping of the acoustic mode is due to the electrical conductivity, the thermal conductivity and the thermoelectric coefficients while the damping of hydromagnetic mode is due to the electrical conductivity. In the case of propagation transverse to the field lines all the transport coefficients contribute to the damping of the hydromagnetic waves.