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arXiv · 1111.6375

The first X-ray survey of Galactic Luminous Blue Variables

Yael Naze·Gregor Rauw·Damien Hutsemekers
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Abstract

Aims: The X-ray emission of massive stars has been studied when these objects are in their main-sequence phase, as well as in their Wolf-Rayet phase. However, the X-ray properties of the transitional Luminous Blue Variable (LBV) phase remain unknown. Methods: Using a dedicated but limited XMM survey as well as archival XMM and Chandra observations, we performed the first X-ray survey of LBVs: about half of the known LBVs or candidate LBVs are studied. Results: Apart from the well known X-ray sources eta Car and Cyg OB2 #12, four additional LBVs are detected in this survey, though some doubt remains on the association with the X-ray source for two of these. For the other LBVs, upper limits on the flux were derived, down to $\log[L_{\rm X}/L_{\rm BOL}]-9.4$ for PCyg. This variety in the strength of the X-ray emission is discussed, with particular emphasis on the potential influence of binarity.

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Yael Naze, Gregor Rauw, Damien Hutsemekers. 2011-11-28. The first X-ray survey of Galactic Luminous Blue Variables. https://doi.org/10.1051/0004-6361%2F201118040

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