Oscillations in Arcturus from Wire Photometry
نویسندگان
چکیده
Observations of the red giant Arcturus (α 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 ∼ 4.1 μHz (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. Subject headings: stars: individuals (α Boo) — stars: oscillations
منابع مشابه
Evidence for Solar-like Oscillations in Arcturus (α Boo)
Abstract. Observations of the red giant Arcturus (α 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 power spectrum has a significant excess of power at low-frequencies. The highest peak is at ∼4.1 μHz, which is in agreement with the ground-based radial velocity and photometry s...
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