Propagational aspects of sunquake waves

We present the results of numerical simulations of impulsively generated se ismic waves excited by a spatially localized impulse source which is connec ted with a nearby solar flare. The solar atmosphere is modeled as a two lay er medium with constant temperature over the photosphere and linearly growi ng temperature below the photosphere. Effects of magnetic fields are neglec ted. Only two dimensional effects are considered. The source is localized s lightly below the photosphere. The numerical results show that the initial pulse of enhanced pressure, which can be connected with the thermal energy release by interaction of flare-generated particles with the sub-photospher ic medium in the flare-loop footpoint, generates an acoustic (seismic) wave . Interaction of the wave with the solar surface produces perturbations reg istered as sunquakes. Typical observationally registered features of the su nquakes, such as characteristic wave signatures and acceleration of the wav e with the distance from the epicenter, are well reproduced with the model developed. It is found that the seismic waves are essentially dispersive an d non-linear. The proposed model provides us with a theoretical basis for s unquake seismology of the solar interior.