EFFECTS OF RADIATIVE LOSSES ON THE WAVE P ROPERTIES IN SOLAR ACTIVE REGIONS

A theory of linear transformation and absorption of different types of nonadiabatic magneto-acoustic-gravity waves in isothermal atmosphere involving the effects of radiative losses is developed. Energy coeffic ients of reflection and absorption of waves are calculated using analy tical solutions of the equations of magnetic hydrodynamics. It is show n that at the level of the solar photosphere where omega(R) approximat e to 1 (omega is the frequency of oscillations and t(R), the radiative relaxation time of the temperature perturbations) the waves interact efficiently with radiation. The effect of the magnetic-field inclinati on on the wave damping is studied. The trapping of the 3-min oscillati ons in the sunspot umbrae and 5-min oscillations in the sunspot penumb rae at the temperature-minimum level is studied. The phase shift and t he amplitude ratio of the velocity and temperature oscillations are ca lculated. It is shown that the phase shift grows rather fast along the sunspot radius. The results obtained can be used to diagnose the sola r plasma in spots and enable solution of the inverse problem of the ma gnetic-field distribution along the spot radius using the observed dia gnostic properties of oscillations.