Observation of Additional Low-Degree Five-Minute Modes of Solar Oscillation,
Abstract
By measuring the difference between the shifts in the Fe 5124 spectrum line from light integrated from a central circular portion of the solar disk and from an annular portion exterior to it, we have been able to detect high-order solar oscillations with degrees l = 3, 4 and 5. The frequencies of the octupole modes agree well with the values obtained from whole-disk measurements at the South Pole. A least-squares fit of the observed frequencies to values interpolated between and extrapolated from the predictions of a sequence of solar models with different chemical compositions selects a model with a helium abundance somewhat greater than 25 per cent by mass.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1982
- Accession Number
- ADA118805
Entities
People
- Douglas Gough
- John M. Wilcox
- Jorgen Christensen-dalsgaard
- Philip Scherrer
Organizations
- Stanford University