Scattering of p-Modes by a Sunspot

Details Scattering of p-Modes by a Sunspot Scattering of p-Modes by a Sunspot

May 1992

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992aas...180.0604b&link_type=abstract

American Astronomical Society, 180th AAS Meeting, #06.04; Bulletin of the American Astronomical Society, Vol. 24, p.737

Physics

Space Physics

Scientific paper

For the first time the scattering phase shifts of solar p-modes from a sunspot have been unambiguously determined. This is made possible by the recent availability of long duration, high duty cycle observations. The results presented here are determined from a Fourier-Hankel decomposition of p-mode amplitudes as measured from a 68 hr subset of a larger set of observations made at the South Pole in 1988. In addition to the detection of the phase shifts, the quality of the data allows the dependence of the p-mode scattering and absorption with azimuthal order, spatial wavenumber and temporal frequency to be independently determined. Thus, unlike previous observations, our measurements of absorption and phase shifts do not represent averages over a range of p-modes. With this information we have for the first time a complete description of the acoustic scattering amplitudes from a large sunspot. Interpretation of these observations requires a suitable theory of the interaction of p-modes and sunspots. However, with the complete scattering amplitudes now available one may apply inverse scattering algorithms, based on a few simplifying assumptions, to deduce a 3-dimensional map of the scattering strength of the active region. This offers the hope that general information about subsurface morphology of active regions might be gained even without a detailed understanding of the physical scattering processes involved. DCB is supported by Air Force URI grant AFOSR-90-0116. The South Pole program is supported in part by National Science Foundation grants DPP87-15791 and 89-17626, and by the Solar Physics Branch of the Space Physics Division of NASA.

Affiliated with

Also associated with

No associations

Rating

Scattering of p-Modes by a Sunspot does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Scattering of p-Modes by a Sunspot, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Scattering of p-Modes by a Sunspot will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1512243