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arXiv · 1012.5128

Temporal Variations of High-Degree Solar p-Modes from GONG and MDI

Olga Burtseva·S. C. Tripathy·R. Howe·K. Jain·F. Hill·R. Bogart·M. C. Rabello-Soares
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Abstract

We study temporal variations in the amplitudes and widths of high-degree acoustic modes in the quiet and active Sun by applying ring-diagram technique to the GONG+ and MDI Dopplergrams during the declining phase of cycle 23. The increase in amplitudes and decrease in line-widths in the declining phase of the solar activity is in agreement with previous studies. A similar solar cycle trend in the mode parameters is also seen in the quiet-Sun regions but with a reduced magnitude. Moreover, the amplitudes obtained from GONG+ data show long-term variations on top of the solar cycle trend.

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Olga Burtseva, S. C. Tripathy, R. Howe, K. Jain, F. Hill, R. Bogart, M. C. Rabello-Soares. 2010-12-23. Temporal Variations of High-Degree Solar p-Modes from GONG and MDI. https://doi.org/10.1088/1742-6596%2F271%2F1%2F012012

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