Simulation of the Effect of Active Regions on Intermediate-Degree Solar Oscillations
Abstract
The effect of active regions on the solar oscillations is simulated by artificially suppressing the velocities in full-disk quiet-sun Doppler images. An image of the active sun is used as a template to mask the regions within which the velocities are reduced by as much as 35%. Two-dimensional - power spectra from both the quiet sun and the masked data are compared. We find that the addition of one large active region does not significantly alter the power in the oscillations, but the presence of several simulated regions decreases the power in the global modes by up to 25%, in agreement with observations. The shapes of the oscillation spectral lines do not substantially change, suggesting that frequencies measured from these spectra will not be significantly altered.
- Publication:
-
Challenges to Theories of the Structure of Moderate-Mass Stars
- Pub Date:
- 1991
- DOI:
- 10.1007/3-540-54420-8_74
- Bibcode:
- 1991LNP...388..253H