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arXiv · 1909.02984

Dissecting the hot bubbles in LMC-N57 with XMM-Newton

I. Ramírez-Ballinas·J. Reyes-Iturbide·J. A. Toalá·M. Rosado
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Abstract

We present a study of the diffuse X-ray emission from the star forming region LMC-N 57 in the Large Magellanic Cloud (LMC). We use archival XMM-Newton observations to unveil in detail the distribution of hot bubbles in this complex. X-ray emission is detected from the central superbubble (SB) DEM L 229, the supernova remnant (SNR) 0532$-$675 and the Wolf-Rayet (WR) bubble DEM L 231 around the WR star Br 48. Comparison with infrared images unveils the powerful effect of massive stars in destroying their nurseries. The distribution of the hot gas in the SNR and the SB display their maxima in regions in contact with the filamentary cold material detected by IR images. Our observations do not reveal extended X-ray emission filling DEM L 231, although several point-like sources are detected in the field of view of this WR nebula. The X-ray properties of Br 48 are consistent with a binary WN4$+$O as proposed by other authors. We modeled the X-ray emission from the SB and found that its X-ray emission can be simply explained by pressure-driven wind model, that is, there is no need to invoke the presence of a SN explosion as previously suggested. The pressure calculations of the hot gas confirms that the dynamical evolution of the SB DEM L 229 is dominated by the stellar winds from the star cluster LH 76.

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I. Ramírez-Ballinas, J. Reyes-Iturbide, J. A. Toalá, M. Rosado. 2019-09-06. Dissecting the hot bubbles in LMC-N57 with XMM-Newton. https://doi.org/10.3847/1538-4357%2Fab44cf

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