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arXiv · 1005.2190

The Lowest Mass Member of the beta Pictoris Moving Group

Emily L. Rice·Jacqueline K. Faherty·Kelle L. Cruz
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Abstract

We present spectral and kinematic evidence that 2MASS J06085283-2753583 (M8.5gamma) is a member of the beta Pictoris Moving Group (BPMG, age ~12 Myr), making it the latest-type known member of this young, nearby association. We confirm low-gravity spectral morphology at both medium and high resolutions in the near-infrared. We present new radial velocity and proper motion measurements and use these to calculate galactic location and space motion consistent with other high-probability members of the BPMG. The predicted mass range consistent with the object's effective temperature, surface gravity, spectral type, and age is 15-35 M_Jup, placing 2MASS 0608-27 well within the brown dwarf mass regime. 2MASS J06085283-2753583 is thus confidently added to the short list of very low mass, intermediate age benchmark objects that inform ongoing searches for the lowest-mass members of nearby young associations.

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Emily L. Rice, Jacqueline K. Faherty, Kelle L. Cruz. 2010-05-12. The Lowest Mass Member of the beta Pictoris Moving Group. https://doi.org/10.1088/2041-8205%2F715%2F2%2Fl165

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