Ultraluminous X-ray sources

The study of ultraluminous X-ray sources (ULXs) has changed dramatically over the last decade. In this review we first describe the most important observations of ULXs in various wavebands , across multiple scales in space , time. We discuss recent progress and current unanswered questions. We consider the range of current theories of ULX properties in the light of this observational progress. Applying these models to neutron-star ULXs offers particularly stringent tests, as this is the unique case where the mass of the accretor is effectively fixed.

Automated summary

The study of ultraluminous X-ray sources (ULXs) has undergone significant changes in the past decade. This review discusses the important observations of ULXs across different wavebands and scales in space and time. The recent progress and unanswered questions are considered, with a focus on the application of current theories to neutron-star ULXs.