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arXiv · 1009.5706

Remnants of massive metal-poor stars: viable engines for ultra-luminous X-ray sources

M. Mapelli·E. Ripamonti·L. Zampieri·M. Colpi
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Abstract

Massive metal-poor stars might end their life by directly collapsing into massive (~25-80 Msun) black holes (BHs). We derive the number of massive BHs (N_BH) that are expected to form per galaxy via this mechanism. We select a sample of 66 galaxies with X-ray coverage, measurements of the star formation rate (SFR) and of the metallicity. We find that N_BH correlates with the number of observed ultra-luminous X-ray sources (ULXs) per galaxy (N_ULX) in this sample. We discuss the dependence of N_ULX and of N_BH on the SFR and on the metallicity.

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M. Mapelli, E. Ripamonti, L. Zampieri, M. Colpi. 2010-09-28. Remnants of massive metal-poor stars: viable engines for ultra-luminous X-ray sources. https://doi.org/10.1002/asna.201011511

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