Chandra Detection of an X-Ray Flare from the Brown Dwarf LP 944-20

  title={Chandra Detection of an X-Ray Flare from the Brown Dwarf LP 944-20},
  author={R. Rutledge and G. Basri and E. Mart{\'i}n and L. Bildsten},
  journal={The Astrophysical Journal},
We have detected a bright X-ray flare from the nearby (d = 5.0 pc) brown dwarf LP 944-20 with the Chandra Advanced CCD Imaging Spectrometer-S. This is an old (500 Myr), rapidly rotating, lithium-bearing M9 object, with a bolometric luminosity of ≈6 × 10^(29) ergs s^(-1). It was detected only by Chandra during an X-ray flare of duration 1-2 hr near the end of a 12.1 hr observation. The peak X-ray luminosity was 1.2^(+0.5)_(-0.3) × 10^(26) ergs s^(-1) in the brightest ≈550 s, corresponding to L_X… Expand

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