A Chandra Observation of a TW Hydrae Association Brown Dwarf
  We present Chandra observations of the young brown dwarf 2MASSW J1207334-393254, which is a probable member of the TW Hya association. Although this substellar object has strong H alpha emission, it has no detected X Ray flux in a fifty kilosecond ACIS-S observation. We place a conservative upper limit of 1.2 x 10^{26} erg/sec on its X-ray luminosity. We compare our M8 target to the similar mass object TWA 5B, which has weaker H alpha emission but strong X-ray emission. We argue our results are consistent with the notion that 2MASSW J1207334-393254 is interacting with a disk. 
John E. Gizis, Ravi Bharat