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arXiv · 1804.09625

A Gaia DR2 Confirmation that 2MASS J12074836-3900043 is a Member of the TW Hya Association

Jonathan Gagné·Eileen C. Gonzales·Jacqueline K. Faherty
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Abstract

We use new data from Gaia DR2 to confirm that the young L1 $\gamma$ candidate member of the TW Hya association (TWA) is now a bona fide member with a model-dependent mass estimate of ~15 $M_{Jup}$. The ambiguous M9 $\gamma$ candidate member 2MASS J12474428---3816464 also gets a higher Bayesian membership probability for TWA membership as a result of Gaia DR2 data and a new radial velocity measurement, but it remains unclear whether it is a true member of TWA or if it is an unrelated young interloper, because it is separated by 4.6 km/s from the locus of TWA members in UVW space.

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Jonathan Gagné, Eileen C. Gonzales, Jacqueline K. Faherty. 2018-04-25. A Gaia DR2 Confirmation that 2MASS J12074836-3900043 is a Member of the TW Hya Association. https://arxiv.org/abs/1804.09625

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