Stellar Model Analysis of the Oscillation Spectrum of eta Bootis Obtained from MOST

D. B. Guenther; T. Kallinger; P. Reegen; W. W. Weiss; J. M. Matthews; R. Kuschnig; S. Marchenko; A. F. J. Moffat; S. M. Rucinski; D. Sasselov; G. A. H. Walker

doi:10.1086/497387

arXiv · astro-ph/0508449

Stellar Model Analysis of the Oscillation Spectrum of eta Bootis Obtained from MOST

D. B. Guenther·T. Kallinger·P. Reegen·W. W. Weiss·J. M. Matthews·R. Kuschnig·S. Marchenko·A. F. J. Moffat·S. M. Rucinski·D. Sasselov·G. A. H. Walker

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Abstract

Eight consecutive low-frequency radial p-modes are identified in the G0 IV star eta Bootis based on 27 days of ultraprecise rapid photometry obtained by the MOST (Microvariability & Oscillations of Stars) satellite. The MOST data extend smoothly to lower overtones the sequence of radial p-modes reported in earlier groundbased spectroscopy by other groups. The lower-overtone modes from the MOST data constrain the interior structure of the model of eta Boo. With the interior fit anchored by the lower-overtone modes seen by MOST, standard models are not able to fit the higher-overtone modes with the same level of accuracy. The discrepancy is similar to the discrepancy that exists between the Sun's observed p-mode frequencies and the p-mode frequencies of the standard solar model. This discrepancy promises to be a powerful constraint on models of 3D convection.

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D. B. Guenther, T. Kallinger, P. Reegen, W. W. Weiss, J. M. Matthews, R. Kuschnig, S. Marchenko, A. F. J. Moffat, S. M. Rucinski, D. Sasselov, G. A. H. Walker. 2005-08-22. Stellar Model Analysis of the Oscillation Spectrum of eta Bootis Obtained from MOST. https://doi.org/10.1086/497387

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