stars: early-type; stars: magnetic fields; X-rays: stars
Abstract :
[en] Early-type stars are well-known to be sources of soft X-rays. However, this high-energy emission can be supplemented by bright and hard X-rays when magnetically confined winds are present. In an attempt to clarify the systematics of the observed X-ray properties of this phenomenon, a large series of Chandra and XMM observations was analyzed, over 100 exposures of 60% of the known magnetic massive stars listed recently by Petit et al. (2013). It is found that the X-ray luminosity is strongly correlated with mass-loss rate, in agreement with predictions of magnetically confined wind models, though the predictions of higher temperature are not always verified. We also investigated the behaviour of other X-ray properties (absorption, variability), yielding additional constraints on models. This work not only advances our knowledge of the X-ray emission of massive stars, but also suggests new observational and theoretical avenues to further explore magnetically confined winds.
Research Center/Unit :
LiSRI - Liège Space Research Institute - ULiège
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Nazé, Yaël ; Université de Liège - ULiège > Groupe d'astrophysique des hautes énergies (GAPHE)
Petit, Véronique; Dept of Physics & Astronomy, Univ. of Delaware, Bartol Res. Inst., Newark, DE 19716, USA
Rinbrand, Melanie; Dept of Physics & Astronomy, Univ. of Delaware, Bartol Res. Inst., Newark, DE 19716, USA
Cohen, David; Dept of Physics & Astronomy, Swarthmore College, Swarthmore, PA 19081, USA
Owocki, Stan; Dept of Physics & Astronomy, Univ. of Delaware, Bartol Res. Inst., Newark, DE 19716, USA
ud-Doula, Asif; Penn State Worthington Scranton, Dunmore, PA 18512, USA
Wade, Gregg; Dept of Physics, RMC, PO Box 17000, Station Forces, Kingston, ON K7K 4B4, Canada)
Language :
English
Title :
The X-ray properties of magnetic massive stars
Publication date :
01 January 2015
Event name :
IAU, symposium 307 (New windows on massive stars: asteroseismology, interferometry, and spectropolarimetry, Geneva)
