Geometric properties of acoustic waves generated by a point source in solar-like interior: effects of acoustic cut-off frequency

TL;DR

This paper derives an analytical solution for acoustic waves generated by a point source in a stratified solar interior, exploring how frequency and depth influence wavefront properties and implications for flare-induced sunquakes.

Contribution

It provides a new analytical model for acoustic wave propagation in the solar interior considering the effects of acoustic cut-off frequency.

Findings

Wavefront properties depend on excitation frequency and depth.

Supersonic pressure perturbations can excite specific wavefront geometries.

Results relate to understanding flare-generated sunquakes.

Abstract

Acoustic waves generated by a point source in stratified plasma are considered in this paper. Analytical parametric solution for monochromatic source is derived for plane-parallel polytrope model of the solar interior. The solution is used to gain insight into the properties of the generated wavefront as a function of excitation frequency and depth. A slowly varying pressure perturbation moving in upper layers of solar photosphere with supersonic speed is also considered. It is shown to excite acoustic waves putting certain restrictions upon their geometry of the generated wavefront. The results are discussed in relation to flare generated sunquakes.