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 day 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 MꙨ and 0:33 ± 0:02 RꙨ. 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 0.49Y0.82 MꙨ, which would make the system at least 3 Gyr old.
The Astrophysical Journal
Scholarly Commons Citation
Vaccaro, T., Rudkin, M., Kawka, A., Vennes, S., Oswalt, T. D., & al., e. (2007). LP 133-373: A New Chromospherically Active Eclipsing dMe Binary with a Distant, Cool White Dwarf Companion. The Astrophysical Journal, 661(2). https://doi.org/10.1086/517872