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Solar-Like Oscillations in beta Hydri: Evidence for Short-Lived High-Amplitude Oscillations

T. R. Bedding·H. Kjeldsen·I. K. Baldry·F. Bouchy·R. P. Butler·F. Carrier·F. Kienzle·G. W. Marcy·S. J. O'Toole·C. G. Tinney
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Abstract

Velocity measurements of the G2 subgiant beta Hyi with both UCLES and CORALIE show a clear excess of power centred at 1.0 mHz. In the UCLES data we find evidence for a short-lived, high-amplitude oscillation event. If confirmed as a feature of subgiants, such `starquakes' would make it harder to measure accurate mode frequencies and perform asteroseismology.

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T. R. Bedding, H. Kjeldsen, I. K. Baldry, F. Bouchy, R. P. Butler, F. Carrier, F. Kienzle, G. W. Marcy, S. J. O'Toole, C. G. Tinney. 2002-02-26. Solar-Like Oscillations in beta Hydri: Evidence for Short-Lived High-Amplitude Oscillations. https://arxiv.org/abs/astro-ph/0202471

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