X-Rays from Superbubbles in the Large Magellanic Cloud. VI. A Sample of Thirteen Superbubbles

The Astrophysical Journal Supplement Series (Impact Factor: 16.24). 04/2001; DOI: 10.1086/321794
Source: arXiv

ABSTRACT We present ROSAT observations and analysis of thirteen superbubbles in the Large Magellanic Cloud. Eleven of these observations have not been previously reported. We have studied the X-ray morphology of the superbubbles, and have extracted and analyzed their X-ray spectra. Diffuse X-ray emission is detected from each of these superbubbles, and X-ray emission is brighter than is theoretically expected for a wind-blown bubble, suggesting that the X-ray emission from the superbubbles has been enhanced by interactions between the superbubble shell and interior SNRs. We have also found significant positive correlations between the X-ray luminosity of a superbubble and its H-alpha luminosity, expansion velocity, and OB star count. Further, we have found that a large fraction of the superbubbles in the sample show evidence of ``breakout'' regions, where hot X-ray emitting gas extends beyond the H-alpha shell. Comment: 25 pages, 8 figures, to be published in Astrophysical Journal Supplement Series

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