Solar Oscillation Frequency Changes on Time Scales of Nine Days
Abstract
We establish that global solar p-mode frequencies can be measured with sufficient precision on time scales as short as nine days to detect activity-related shifts. Using ten years of GONG data, we report that mode-mass and error-weighted frequency shifts derived from nine days are significantly correlated with the strength of solar activity and are consistent with long duration measurements from GONG and the MDI/SOHO instrument. However, the correlation varies from year to year and appears to be a complex phenomena. For the short-duration observations, the analysis indicates a higher sensitivity to activity. We also find that magnetic indices behave differently in the rising and falling phases of the activity cycle.
Cite
@article{arxiv.astro-ph/0608348,
title = {Solar Oscillation Frequency Changes on Time Scales of Nine Days},
author = {S. C. Tripathy and F. Hill and K. Jain and J. W. Leibacher},
journal= {arXiv preprint arXiv:astro-ph/0608348},
year = {2009}
}
Comments
Major changes, additional figures and tables. Accepted for publication in Solar physics