THE SOURCE OF SOLAR HIGH-FREQUENCY ACOUSTIC MODES - THEORETICAL EXPECTATIONS

The source exciting the solar p-modes is likely to be acoustic noise generated in the top part of the Sun's convection zone. If so, then simple arguments suggest that most of the emitted energy may come from rare localized events that are well separated from one another in space and time. This note describes the acoustic emission that would be expected from such events, based on a ray-theory analysis. Most of the acoustic energy is found to emerge very close to the source, so that observations to identify emission events will require high spatial resolution. If emission events could be observed in sufficient detail, they would help answer questions about the source of the solar p-modes, the mechanism by which p-modes appear at frequencies above the photospheric acoustic cutoff frequency, and the structure and dynamics of the solar envelope just below the visible surface.