The First Substellar Subdwarf? Discovery of a Metal-poor L Dwarf with Halo Kinematics

  title={The First Substellar Subdwarf? Discovery of a Metal-poor L Dwarf with Halo Kinematics},
  author={Adam J. Burgasser and J. Davy Kirkpatrick and Adam S. Burrows and James William Liebert and I. Neill Reid and John E. Gizis and Mark R. McGovern and Lisa Prato and Ian S. McLean},
  journal={The Astrophysical Journal},
  pages={1186 - 1192}
We present the discovery of the first L-type subdwarf, 2MASS J05325346+8246465. This object exhibits enhanced collision-induced H2 absorption, resulting in blue near-infrared (NIR) colors (J-Ks = 0.26 ± 0.16). In addition, strong hydride bands in the red optical and NIR, weak TiO absorption, and an optical/J-band spectral morphology similar to the L7 DENIS 0205-1159AB imply a cool, metal-deficient atmosphere. We find that 2MASS 0532+8246 has both a high proper motion, μ = 2.″60 ± 0.″15 yr-1… 

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