Masses and Radii of Low-Mass Stars: Theory versus Observations

Abstract

Eclipsing binaries with M-type components are still rare objects. Strong observational biases have made that today only a few eclipsing binaries with component masses below 0.6 Msun and well-determined fundamental properties are known. However, even in these small numbers the detailed comparison of the observed masses and radii with theoretical predictions has revealed large disagreements. Current models seem to predict radii of stars in the 0.4-0.8 Msun range to be some 5-15% smaller than observed. Given the high accuracy of the empirical measurements (a few percent in both mass and radius), these differences are highly significant. I review all the observational evidence on the properties of M-type stars and discuss a possible scenario based on stellar activity to explain the observed discrepancies.

8 pages, 1 figure, proceedings of the meeting "Close Binaries in the 21st Century"

References in corpus (6)

• GU Boo: A New 0.6 Msun Detached Eclipsing Binary
• Doppler follow-up of OGLE transiting companions in the Galactic bulge
• The Eclipsing Binary V1061 Cygni: Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars
• Doppler follow-up of OGLE planetary transit candidates in Carina
• The shortest period M-dwarf eclipsing system BW3 V38, II: determination of absolute elements
• A New Detached M Dwarf Eclipsing Binary

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