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A comprehensive asteroseismic modelling of the high-amplitude delta Scuti star RV Arietis

R. Casas·J. C. Suarez·A. Moya·R. Garrido
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Abstract

We present a comprehensive asteroseismic study of the double-mode high-amplitude delta Scuti star HD 187642 (RV Arietis). The modelling includes some of the most recent techniques: 1) effects of rotation on both equilibrium models and adiabatic oscillation spectrum, 2) non-adiabatic study of radial and non-radial modes, 3) relationship between the fundamental radial mode and the first overtone in the framework of Petersen diagrams. The analysis reveals that two of the observed frequencies are very probably identified as the fundamental and first overtone radial modes. Analysis of the colour index variations, together with theoretical non-adiabatic calculations, points to models in the range of [7065,7245] K in effective temperature and of [1190, 1270] Myr in stellar age. These values were found to be compatible with those obtained using the three other asteroseismic techniques.

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R. Casas, J. C. Suarez, A. Moya, R. Garrido. 2006-05-25. A comprehensive asteroseismic modelling of the high-amplitude delta Scuti star RV Arietis. https://doi.org/10.1051/0004-6361%3A20065054

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