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The dM4.5e star G124-62 and its binary L dwarf companion DENIS-P J1441-0945: Common proper motion, distance, age, and masses

Andreas Seifahrt·Eike Guenther·Ralph Neuhaeuser
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Abstract

We present astrometric and photometric measurements of the field binary L1 dwarf DENIS-P J1441-0945. Analysis of archival HST images and photometric parallax measurements give a distance of 34+/-7 pc and a proper motion close to that of the nearby high proper motion star G124-62. Comparison of SuperCOSMOS and 2MASS images confirms that these objects form a common proper motion pair, while spectroscopy of G124-62 shows it to be a dM4.5e star. The kinematics show that this system is a member of the Hyades supercluster. The resulting age constraints for the system are 500--800 Myr and the mass of each component of DENIS-P J1441-0945 is 0.072 (+0.010/-0.018) M_sun.

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Andreas Seifahrt, Eike Guenther, Ralph Neuhaeuser. 2005-05-17. The dM4.5e star G124-62 and its binary L dwarf companion DENIS-P J1441-0945: Common proper motion, distance, age, and masses. https://doi.org/10.1051/0004-6361%3A20041902

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