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LP133-373: A New Chromospherically Active Eclipsing dMe Binary with a Distant, Cool White Dwarf Companion

T. R. Vaccaro·M. Rudkin·A. Kawka·S. Vennes·T. D. Oswalt·I. Silver·M. Wood·J. A. Smith
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Abstract

We report the discovery of the partially eclipsing binary LP 133-373. Nearly identical eclipses along with observed photometric colors and spectroscopy indicate that it is a pair of chromospherically active dM4 stars in a circular 1.6 d orbit. Light and velocity curve modeling to our differential photometry and velocity data show that each star has a mass and radius of 0.340+/-0.014 M_sun and 0.33+/-0.02 R_sun. The binary is itself part of a common proper motion pair with LP 133-374 a cool DC or possible DA white dwarf with a mass of 0.49-0.82 M_sun, which would make the system at least 3 Gyr old.

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T. R. Vaccaro, M. Rudkin, A. Kawka, S. Vennes, T. D. Oswalt, I. Silver, M. Wood, J. A. Smith. 2007-03-03. LP133-373: A New Chromospherically Active Eclipsing dMe Binary with a Distant, Cool White Dwarf Companion. https://doi.org/10.1086/517872

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