2005/07/19 by John E. Gizis, Harry L. Shipman, H. L. Shipman +2 · 3 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/462414
published as Astrophys.J.630:L89-L92,2005 · 8 pages, to appear in Astrophysical Journal Letters
arxiv created 2005/07/19 · openalex publication_date 2005/08/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We analyze an HST/STIS ultraviolet spectrum of the young brown dwarf 2MASSW J1207334-393254, a member of the ten million-year old TW Hya Association that has a planetary-mass companion. We detect and identify numerous emission lines. CIV and other ions are seen that arise in hot gas. We identify a series of lines with Lyman-pumped H2 molecular lines, indicating that cool gas is also present. Overall, this substellar object shows many of the same characteristics as classical T Tauri stars. We interpret our results as direct evidence of accretion from a circumstellar gas disk, consistent with previous claims. The lack of SiIV emission from the accreting gas indicates that silicon has been depleted into grains.