Evidence for colliding winds in WR 25 from XMM-Newton observations of X-ray variability

被引：27

作者：

Pollock, AMT

Corcoran, MF

机构：

[1] European Space Agcy, European Space Astron Ctr, XMM Newton Sci Operat Ctr, Madrid, Spain

[2] Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA

[3] Univ Space Res Assoc, Seabrook, MD 20706 USA

来源：

ASTRONOMY & ASTROPHYSICS | 2006年 / 445卷 / 03期

关键词：

X-rays : stars; stars : Wolf-Rayet; stars : individual : WR 25; stars; winds; outflows; stars : binaries : general;

D O I：

10.1051/0004-6361:20053496

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The Wolf-Rayet star WR 25 in the Carina Nebula is a surprisingly bright X-ray source, and amongst the brightest WR stars in X-rays. It is a suspected binary star, though its binary nature has been a matter of controversy. We report here observations of WR 25 from the XMM-Newton archive which showed an increase in X-ray luminosity of more than a factor of two. The X-ray absorption also increased. Such a large change in X-ray output is unknown in single massive stars, though large changes in X-ray brightness are seen in binaries. The most likely explanation of the observed X-ray variability is as a result of colliding- wind emission in a moderately eccentric binary with a period of about 4 years. The next periastron passage is expected in 2007. The X-ray spectrum is similar to that of the archetype colliding-wind binary WR 140.

引用

页码：1093 / 1097

页数：5

共 9 条

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