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arXiv · 1511.00861

Diffuse X-ray Emission within Wolf-Rayet Nebulae

J. A. Toalá·M. A. Guerrero·Y. -H. Chu·S. J. Arthur·R. A. Gruendl
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Abstract

We discuss our most recent findings on the diffuse X-ray emission from Wolf-Rayet (WR) nebulae. The best-quality X-ray observations of these objects are those performed by XMM-Newton and Chandra towards S308, NGC2359, and NGC6888. Even though these three WR nebulae might have different formation scenarios, they all share similar characteristics: i) the main plasma temperatures of the X-ray-emitting gas is found to be $T$=[1-2]$\times$10$^{6}$ K, ii) the diffuse X-ray emission is confined inside the [O III] shell, and iii) their X-ray luminosities and electron densities in the 0.3-2.0~keV energy range are $L_\mathrm{X}\approx$10$^{33}$-10$^{34}$~erg~s$^{-1}$ and $n_\mathrm{e}\approx$0.1-1~cm$^{-3}$, respectively. These properties and the nebular-like abundances of the hot gas suggest mixing and/or thermal conduction is taking an important role reducing the temperature of the hot bubble.

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J. A. Toalá, M. A. Guerrero, Y. -H. Chu, S. J. Arthur, R. A. Gruendl. 2015-11-03. Diffuse X-ray Emission within Wolf-Rayet Nebulae. https://arxiv.org/abs/1511.00861

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