English

Brown Dwarfs and the TW Hya Association

Astrophysics 2009-12-08 v1

Abstract

I report the results of a survey for low-mass (0.030 <~ M <~ 0.013 M_solar) brown dwarfs in the direction of the TW Hya association using 2MASS. Two late-M dwarfs show signs of low surface gravity and are strong candidates to be young, very-low-mass (M ~ 0.025 M_solar) brown dwarfs related to the TW Hya association. 2MASSW J1207334-393254 is particularly notable for its strong H alpha emission. The number of detected brown dwarfs is consistent with the substellar mass function in richer star formation environments. Newly identified late-M and L dwarfs in the field are also discussed. Unusual objects include an L dwarf with strong H alpha emission, a possible wide M8/M9 triple system, and a possible L dwarf companion to an LHS star.

Keywords

Cite

@article{arxiv.astro-ph/0204342,
  title  = {Brown Dwarfs and the TW Hya Association},
  author = {John E. Gizis},
  journal= {arXiv preprint arXiv:astro-ph/0204342},
  year   = {2009}
}

Comments

Accepted to Ap.J., 22 pages