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arXiv · 0811.1053

Discovery of a Low-Mass Companion to the Solar-Type Star TYC 2534-698-1

Stephen R. Kane·Suvrath Mahadevan·William D. Cochran·Rachel A. Street·Sivarani Thirupathi·Gregory W. Henry·Michael H. Williamson
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Abstract

Brown dwarfs and low-mass stellar companions are interesting objects to study since they occupy the mass region between deuterium and hydrogen burning. We report here the serendipitous discovery of a low-mass companion in an eccentric orbit around a solar-type main sequence star. The stellar primary, TYC 2534-698-1, is a G2V star that was monitored both spectroscopically and photometrically over the course of several months. Radial velocity observations indicate a minimum mass of 0.037 M_solar and an orbital period of ~103 days for the companion. Photometry outside of the transit window shows the star to be stable to within ~6 millimags. The semi-major axis of the orbit places the companion in the 'brown dwarf desert' and we discuss potential follow-up observations that could constrain the mass of the companion.

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Stephen R. Kane, Suvrath Mahadevan, William D. Cochran, Rachel A. Street, Sivarani Thirupathi, Gregory W. Henry, Michael H. Williamson. 2008-11-06. Discovery of a Low-Mass Companion to the Solar-Type Star TYC 2534-698-1. https://doi.org/10.1088/0004-637x%2F692%2F1%2F290

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