The ultra-luminous X-ray phase as a progenitor channel for LIGO–Virgo–KAGRA sources

The gravitational-wave signals detected by the LIGO, Virgo, and KAGRA (LVK) gravitational-wave network provide valuable insights into the masses, distances, and sky locations of compact binary systems. However, the evolutionary origins of these systems remain uncertain. In this study, we investigate ultra-luminous X-ray sources (ULXs) as potential progenitors of the double compact objects (DCOs) detected by the LVK collaboration. Using a population of ULXs generated in our previous work, we model the formation of DCOs with ULX priors and compare their properties with those inferred from LVK observations. Our results indicate that DCOs formed through the ULX channel can account primarily for the low-mass end of the LVK-detected population.