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Oscillations in Arcturus from WIRE photometry

A. Retter·T. Bedding·D. L. Buzasi·H. Kjeldsen·L. L. Kiss
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Abstract

Observations of the red giant Arcturus (Alpha Boo) obtained with the star tracker on the Wide Field Infrared Explorer (WIRE) satellite during a baseline of 19 successive days in 2000 July-August are analysed. The amplitude spectrum has a significant excess of power at low-frequencies. The highest peak is at about 4.1 micro-Hz (2.8 d), which is in agreement with previous ground-based radial velocity studies. The variability of Arcturus can be explained by sound waves, but it is not clear whether these are coherent p-mode oscillations or a single mode with a short life-time.

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A. Retter, T. Bedding, D. L. Buzasi, H. Kjeldsen, L. L. Kiss. 2003-08-25. Oscillations in Arcturus from WIRE photometry. https://doi.org/10.1086/377211

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