A Massive Runaway Star from 30 Doradus

Evans, C. J.; Walborn, N. R.; Crowther, P. A.; Hénault-Brunet, V.; Massa, D.; Taylor, W. D.; Howarth, I. D.; Sana, H.; Lennon, D. J.; van Loon, J. Th.
The Astrophysical Journal Letters, Volume 715, Issue 2, pp. L74-L79 (2010).


We present the first ultraviolet (UV) and multi-epoch optical spectroscopy of 30 Dor 016, a massive O2-type star on the periphery of 30 Doradus in the Large Magellanic Cloud. The UV data were obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope as part of the Servicing Mission Observatory Verification program after Servicing Mission 4, and reveal #016 to have one of the fastest stellar winds known. From analysis of the C IV λλ1548-51 doublet we find a terminal velocity, v = 3450 ± 50 km s-1. Optical spectroscopy is from the VLT-FLAMES Tarantula Survey, from which we rule out a massive companion (with 2 days < P < 1 yr) to a confidence of 98%. The radial velocity of #016 is offset from the systemic value by -85 km s-1, suggesting that the star has traveled the 120 pc from the core of 30 Doradus as a runaway, ejected via dynamical interactions.

Based on observations obtained at the European Southern Observatory Very Large Telescope in program 184.D-0222 and with the NASA/ESA Hubble Space Telescope in program 11484, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.