We propose to investigate the X-ray properties of HD16691, an O4 supergiantbelieved to be a transition object between O and Wolf-Rayet stars. Recentspectroscopic investigations by our team in the visible domain revealed astellar wind affected by a large scale corotating structure, perhaps related tothe interplay between the stellar magnetic field and the plasma outflow. Thisobject constitutes therefore a valuable target for investigating the role of thepotential magnetic confinement of the stellar wind. In addition, most of theO-type stars observed so far in X-rays belong to spectral types later than O5.An XMM-Newton study of HD16691 will therefore contribute to complete the pictureof the X-ray properties of early-type stars.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2011-08-21T07:35:41Z/2011-08-21T13:37:40Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Dr Michael De Becker, 2012, 'HD16691: an extreme O-type supergiant with magnetically confined windquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-pem0fs2
