X-Ray Spectroscopy Of The O2 If* Star Hd 93129a
Four Decades Of Research On Massive Stars: Proceedings Of A Scientific Meeting In Honor Of Anthony F.J. Moffat
ASP Conference Series
The O2 If* star, HD 93129A, is among the earliest in the Galaxy and has one of the strongest winds of any 0 star. In this paper, we show that its hard and strong X-ray emission can be understood in terms of the standard embedded wind shock paradigm for effectively single, hot, massive stars. Wind attenuation of the intrinsically soft X-ray emission is an important effect, which explains the hardness of the observed X-rays. We measure the degree of wind absorption in two different ways in order to derive a mass-loss rate of roughly 6 x 10(-6) M-circle dot yr(-1). This value is consistent with the observed H alpha line if a clumping factor of f(cl) = 12 is assumed.
Astronomical Society of the Pacific
L. Drissen, C. Robert, N. St. Louis, and A. F.J. Moffat, eds.
Four Decades Of Research On Massive Stars: A Scientific Meeting In Honor Of Anthony F.J. Moffat
July 11-15, 2011
Auberge Lac Taureau, St-Michel-des-Saints, Québec, Canada
David H. Cohen.
"X-Ray Spectroscopy Of The O2 If* Star Hd 93129a".
Four Decades Of Research On Massive Stars: Proceedings Of A Scientific Meeting In Honor Of Anthony F.J. Moffat.