Volume 408, Number 2, September III 2003
|Page(s)||729 - 736|
|Published online||17 November 2003|
Study of p-mode excitation and damping rate variations from IRIS++ observations
Laboratoire Universitaire d'Astrophysique de Nice, Université de Nice-Sophia Antipolis, 06108 Nice Cedex 2, France
2 School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
3 Themis, Instituto de Astrofísica de Canarias, 38701, La Laguna, Tenerife, Spain
4 High Altitude Observatory, NCAR, PO Box 3000, Boulder, CO 80307, USA
Corresponding author: D. Salabert, email@example.com
Accepted: 4 June 2003
11 years of low degree helioseismic data collected by the IRIS++ network (International Research of the Interior of the Sun) have been analyzed. The epoch covered (mid-1989 to end-1999) spans the maximum and the falling phase of solar cycle 22 and the rising phase of the current solar cycle 23. Annual timeseries with an overlap of 6 months are used to study the variations with solar activity of the p-mode frequencies , heights , and linewidths , taking into account the effects of the window function. These are used to infer variations in the velocity power and the energy supply rate which relate to changes in the excitation and the damping of the modes. We find global changes over the range 2600 Hz of about -26%, 11%, -11% for the heights, the linewidths, and the velocity power respectively, and a constant energy supply to the modes.
Key words: Sun: helioseismology / Sun: activity
© ESO, 2003
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.