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arXiv · 1412.3694

X-rays from the episodic dust maker WR 137

Svetozar A. Zhekov
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Abstract

We present an analysis of the XMM-Newton observation of the episodic dust maker WR 137. Global spectral fits show that its X-ray spectrum is well matched by a two-temperature optically-thin plasma emission (kT_1 ~ 0.4 keV and kT_2 ~ 2.2 keV). If we adopt the colliding stellar wind (CSW) picture for this wide WR+O binary, the theoretical CSW spectra match well the shape of the observed X-ray spectrum of WR 137 but they overestimate the observed flux (emission measure) by about two orders of magnitude. To reconcile the model predictions with observations, the mass loss of \WR must be reduced considerably (by about an order of magnitude) with respect to its currently accepted value. In all the spectral fits, the derived X-ray absorption is consistent with the optical extinction to WR 137.

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Svetozar A. Zhekov. 2014-12-11. X-rays from the episodic dust maker WR 137. https://doi.org/10.1093/mnras%2Fstu2642

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