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arXiv · 0912.2834

New insights on the interior of solar-like pulsators thanks to CoRoT: the case of HD 49385

S. Deheuvels·E. Michel
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Abstract

The high performance photometric data obtained with space mission CoRoT offer the opportunity to efficiently constrain our models for the stellar interior of solar-like pulsating stars. On the occasion of the analysis of the oscillations of solar-like pulsator HD 49385, a G0-type star in an advanced stage of evolution, we revisit the phenomenon of the avoided crossings. Christensen-Dalsgaard proposed a simple analogy to describe an avoided crossing between two modes. We here present an extension of this analogy to the case of $n$ modes, and show that it should lead, in certain cases, to a characteristic behavior of the eigenfrequencies, significantly different from the $n=2$ case. This type of behavior seems to be observed in HD 49385, from which we infer that the star should be in a Post Main Sequence phase.

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S. Deheuvels, E. Michel. 2009-12-15. New insights on the interior of solar-like pulsators thanks to CoRoT: the case of HD 49385. https://doi.org/10.1007/s10509-009-0216-2

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