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Solar-like oscillations in the metal-poor subgiant nu Indi: constraining the mass and age using asteroseismology

Timothy R. Bedding·R. Paul Butler·Fabien Carrier·Francois Bouchy·Brendon J. Brewer·Patrick Eggenberger·Frank Grundahl·Hans Kjeldsen·Chris McCarthy·Tine Bjorn Nielsen·Alon Retter·Christopher G. Tinney
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Abstract

Asteroseismology is a powerful method for determining fundamental properties of stars. We report the first application to a metal-poor object, namely the subgiant star nu Ind. We measured precise velocities from two sites, allowing us to detect oscillations and infer a large frequency separation of Delta_nu = 24.25 +/- 0.25 microHz. Combining this value with the location of the star in the H-R diagram and comparing with standard evolutionary models, we were able to place constraints on the stellar parameters. In particular, our results indicate that nu Ind has a low mass (0.85 +/- 0.04 M_sun) and is at least 9 Gyr old.

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Timothy R. Bedding, R. Paul Butler, Fabien Carrier, Francois Bouchy, Brendon J. Brewer, Patrick Eggenberger, Frank Grundahl, Hans Kjeldsen, Chris McCarthy, Tine Bjorn Nielsen, Alon Retter, Christopher G. Tinney. 2006-04-21. Solar-like oscillations in the metal-poor subgiant nu Indi: constraining the mass and age using asteroseismology. https://doi.org/10.1086/505295

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