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arXiv · 1207.3090

Reevaluating the Mass-Radius Relation for Low-Mass, Main Sequence Stars

Gregory A. Feiden·Brian Chaboyer
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Abstract

We examine the agreement between the observed and theoretical low-mass (< 0.8 solar masses) stellar main sequence mass-radius relationship by comparing detached eclipsing binary (DEB) data with a new, large grid of stellar evolution models. The new grid allows for a realistic variation in the age and metallicity of the DEB population, characteristic of the local galactic neighborhood. Overall, our models do a reasonable job of reproducing the observational data. A large majority of the models match the observed stellar radii to within 4%, with a mean absolute error of 2.3%. These results represent a factor of two improvement compared to previous examinations of the low-mass mass-radius relationship. The improved agreement between models and observations brings the radius deviations within the limits imposed by potential starspot-related uncertainties for 92% of the stars in our DEB sample.

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Gregory A. Feiden, Brian Chaboyer. 2012-07-12. Reevaluating the Mass-Radius Relation for Low-Mass, Main Sequence Stars. https://doi.org/10.1088/0004-637x/757/1/42

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