The XMM-Newton view of the yellow hypergiant IRC +10420 and its surroundings


De Becker M., Hutsem├ękers D., Gosset, E.

Department of Astrophysics, Geophysics and Oceanography, University of Li├Ęge

Among evolved massive stars likely in transition to the Wolf-Rayet phase, IRC +10420 is probably one of the most enigmatic. It belongs to the category of yellow hypergiants and it is characterized by quite high mass loss episodes. Even though IRC +10420 benefited of many observations in several wavelength domains, it has never been a target for an X-ray observatory. We report here on the very first dedicated observation of IRC +10420 in X-rays, using the XMM-Newton satellite. Even though the target is not detected, we derive X-ray flux upper limits of the order of 1--3 10^-14 erg cm^-2 s^-1 (between 0.3 and 10.0 keV), and we discuss the case of IRC +10420 in the framework of emission models likely to be adequate for such an object. Using the Optical/UV Monitor on board XMM-Newton, we present the very first upper limits of the flux density of IRC +10420 in the UV domain (between 1800 and 2250 A, and between 2050 and 2450 A). Finally, we also report on the detection in this field of 10 X-ray and 7 UV point sources, and we briefly discuss their properties and potential counterparts at longer wavelengths.

Reference: 2014, New Astronomy (in press)
Status: Manuscript has been accepted

Weblink: http://hdl.handle.net/2268/160591

Comments: ArXiv link: http://arxiv.org/abs/1401.0707

Email: debecker@astro.ulg.ac.be