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arXiv · 2105.10537

Ultraluminous X-Ray Sources

S. N. Fabrika·K. E. Atapin·A. S. Vinokurov·O. N. Sholukhova
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Abstract

Ultraluminous X-ray sources (ULXs) were identified as a separate class of objects in 2000 based on data from the Chandra X-Ray Observatory. These are unique objects: their X-ray luminosities exceed the Eddington limit for a typical stellar-mass black hole. For a long time, the nature of ULXs remained unclear. However, the gradual accumulation of data, new results of X-ray and optical spectroscopy, and the study of the structure and energy of nebulae surrounding ULXs led to the understanding that most of the ultraluminous X-ray sources must be supercritical accretion disks like SS 433. The discovery of neutron stars in a number of objects only increased the confidence of the scientific community in the conclusions obtained, since the presence of neutron stars in such systems clearly indicates a supercritical accretion regime. In this review, we systematize the main facts about the observational manifestations of ULXs and SS 433 in the X-ray and optical ranges and discuss their explanation from the point of view of the supercritical accretion theory.

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S. N. Fabrika, K. E. Atapin, A. S. Vinokurov, O. N. Sholukhova. 2021-05-21. Ultraluminous X-Ray Sources. https://doi.org/10.1134/s1990341321010077

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