Energy Distribution of High-Degree Solar Oscillations

Lead Investigator:
Martin F. Woodard, National Solar Observatory

Team Members:
Pawan Kumar, Institute for Advanced Study

Technical Summary:

We propose to determine the power distribution of solar p- and f-modes as a function of spherical harmonic degree. According to the work of Goldreich, Kumar, and Murray, the surface velocity power is expected to increase by about a factor of 2 between l = 50 and l = 1000(for modes of fixed temporal frequency).

Two ground-based observational studies (Kaufman ~1990, Korzennik 1990) suggest that the p- and f-mode power actually decreases with l in this l range. However, these conclusions are questionable due to uncertainties in corrections which were made for atmospheric seeing. The MDI velocity power spectra can be determined quite accurately up to l of about 1000 and will provide a good check on the stochastic excitation theory of p-modes.