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NSVS01031772: A New 0.50+0.54 Msun Detached Eclipsing Binary

Mercedes Lopez-Morales·Jerome A. Orosz·J. Scott Shaw·Lauren Havelka·Maria Jesus Arevalo·Travis McIntyre·Carlos Lazaro
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Abstract

We report the discovery of a new detached eclipsing binary known as NSVS01031772 with component masses M_1= 0.5428 +/- 0.0027Msun, M_2= 0.4982 +/- 0.0025Msun, and radii R_1= 0.5260 +/- 0.0028Rsun, R_2= 0.5088 +/- 0.0030Rsun. The system has an orbital period of 0.3681414(3) days and an apparent magnitude V ~ 12.6. The estimated effective temperatures of the stars are T_eff1 = 3615 +/- 72K and T_eff2 = 3513 +/- 31K. The space velocities of the system suggest that it is a main sequence binary and with a metallicity that is approximately solar. The two stars in this binary are located in a region of the Mass-Radius relation where no accurate observational data were previously available. Similarly to other low-mass binaries recently studied, the radius of each star in NSVS01031772 exceeds the best evolutionary model predictions by about 8.5% on average.

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Mercedes Lopez-Morales, Jerome A. Orosz, J. Scott Shaw, Lauren Havelka, Maria Jesus Arevalo, Travis McIntyre, Carlos Lazaro. 2006-10-07. NSVS01031772: A New 0.50+0.54 Msun Detached Eclipsing Binary. https://arxiv.org/abs/astro-ph/0610225

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