Testing Low-Mass Stellar Models: Three New Detached Eclipsing Binaries below 0.75 Msun

Mercedes Lopez-Morales; J. Scott Shaw

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arXiv · astro-ph/0603748

Testing Low-Mass Stellar Models: Three New Detached Eclipsing Binaries below 0.75 Msun

Mercedes Lopez-Morales·J. Scott Shaw

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Abstract

Full tests to stellar models below 1 Msun have been hindered until now by the scarce number of precise measurements of the stars' most fundamental parameters: their masses and radii. With the current observational techniques, the required precision to distinguish between different models (errors < 2-3 %) can only be achieved using detached eclipsing binaries where 1) both stars are similar in mass, i.e. q = M1/M2 ~ 1.0, and 2) each star is a main sequence object below 1 Msun. Until 2003 only three such binaries had been found and analyzed in detail. Two new systems were published in 2005 (Creevey et al.; Lopez-Morales & Ribas), almost doubling the previous number of data points. Here we present preliminary results for 3 new low-mass detached eclipsing binaries. These are the first studied systems from our sample of over 41 new binaries (Shaw & Lopez-Morales, this proceedings). We also provide an updated comparison between the Mass-Radius and the Mass-Teff relations predicted by the models and the observational data from detached eclipsing binaries.

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Mercedes Lopez-Morales, J. Scott Shaw. 2006-03-28. Testing Low-Mass Stellar Models: Three New Detached Eclipsing Binaries below 0.75 Msun. https://arxiv.org/abs/astro-ph/0603748

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