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.

根据钱德拉X射线天文台提供的数据，2000年将超发光X射线源（ULX）识别为单独的一类物体。这些是独特的物体：对于典型的恒星质量黑洞，它们的X射线光度超过了爱丁顿极限。长期以来，ULX的性质仍不清楚。但是，数据的逐步积累，X射线和光谱学的新结果以及对ULX周围星云的结构和能量的研究使人们认识到，大多数超发光X射线源必须是超临界吸积盘，如SS 433.在许多物体中发现中子星只会增加科学界对所得出结论的信心，因为在这样的系统中中子星的存在清楚地表明了超临界增生机制。在这篇评论中，