Volume 445, Number 3, January III 2006
|Page(s)||1093 - 1097|
|Published online||03 January 2006|
Evidence for colliding winds in from XMM-Newton observations of X-ray variability
European Space Agency, Science Operations Centre, European Space Astronomy Centre, Apartado 50727, Villafranca del Castillo, 28080 Madrid, Spain
2 Laboratory for High Energy Astrophysics, Goddard Space Flight Center, Greenbelt, MD 20771, USA
3 Universities Space Research Association, 7501 Forbes Blvd, Ste 206, Seabrook, MD 20706, USA
Accepted: 8 September 2005
The Wolf-Rayet star 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 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 .
Key words: X-rays: stars / stars: Wolf-Rayet / stars: individual: / stars: winds, outflows / stars: binaries: general
© ESO, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.