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arXiv · 1712.08658

Discovery of a Possible Early-T Thick-Disk Subdwarf from the AllWISE2 Motion Survey

Kendra Kellogg·J. Davy Kirkpatrick·Stanimir Metchev·Jonathan Gagne·Jacqueline Faherty
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Abstract

We have discovered a potential T0 $\pm$ 1 subdwarf from a search for sources in the AllWISE2 Motion Survey that do not have counterparts in surveys at shorter wavelengths. With a tangential velocity of $\sim$170 kms, this object - WISE J071121.36-573634.2 - has kinematics that are consistent with the thick-disk population of the Milky Way. Spectral fits suggest a low-metallicity for this object but also allow for the possibility of unresolved multiplicity. If WISE J0711-5736 is indeed an sdT0 dwarf, it would be only the second early-T subdwarf discovered to date.

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Kendra Kellogg, J. Davy Kirkpatrick, Stanimir Metchev, Jonathan Gagne, Jacqueline Faherty. 2017-12-22. Discovery of a Possible Early-T Thick-Disk Subdwarf from the AllWISE2 Motion Survey. https://doi.org/10.3847/1538-3881%2Faaa3f2

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