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arXiv · 1302.2238

The missing link between ultraluminous X-ray sources and metallicity

M. Mapelli
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Abstract

The nature of ultraluminous X-ray sources (ULXs) is still debated. Recent studies show that metal-poor massive stars can collapse into massive stellar black holes (MSBHs), that is black holes with mass > 25 Msun. Such MSBHs are sufficiently massive to explain most ULXs without requiring substantial violations of the Eddington limit. The recent finding of an anti-correlation between metallicity of the environment and number of ULXs per galaxy supports this hypothesis. We present the results of recent N-body simulations, including metallicity dependent stellar evolution, and we discuss the main pathways to produce X-ray binaries powered by MSBHs.

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M. Mapelli. 2013-02-09. The missing link between ultraluminous X-ray sources and metallicity. https://arxiv.org/abs/1302.2238

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