New Observations of the Sun: Helioseismology and the Photospheric Magnetic Field
Abstract
In the past several years the interior of the Sun has become accessible to direct observation via helioseismology. The Michelson Doppler Imager (MDI) experiment aboard the Solar and Heliosperic Observatory (SOHO) spacecraft has allowed inferrences of solar interior conditions from the upper few thousand km to near the solar core. In addition to global scale observations, the MDI instrument allows local helioseismology techniques to be used to probe local sound speed variations and flows in the near surface regions just beneath supergranulation and sunspots. The MDI instrument also obtains a near continuous record of the photospheric magnetic field without degradation from the Earht's atmosphere. These observations reveal a new picture of magnetic field evolution. This paper will review the observational methods, basic analysis techniques, and present results obtained from the first two years of operation of MDI. Further information about the SOHO mission and MDI observations in particular can be found at <A HREF=http://soi.stanford.edu>http://soi.stanford.edu</A>.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- November 1998
- Bibcode:
- 1998APS..DPPH4I202S