Solar p-modes and surface magnetic fields:: Is there an acoustic emission?: MDI/SOHO observations

We study the effect of magnetism on the surface amplitude of p-modes by creating power maps using Doppler velocity, line-depth and continuum intensity data taken by the Michelson Doppler Interferometer (MDI) instrument on board SOHO. This analysis, using proper tracking procedures, of MDI line-depth data and its comparison with the simultaneous Doppler velocity data is the first such analysis. All three datasets show that the p-mode power is suppressed in the magnetic region with suppression increasing with field strength. However, in the high-frequency range, the power is enhanced in the Doppler velocity and line-depth data but not in continuum intensity. This enhancement, when present, appears to be in intermediate field strength elements in the immediate vicinity of a magnetically active region.