White Dwarf-Black Hole Mergers Linked to Low Redshift Gamma-ray Bursts

Recent research by Nicole M. Lloyd-Ronning, Jarrett L. Johnson, Phoebe R. Upton Sanderbeck, Makana Silva, and Roseanne M. Cheng explores the role of white dwarf-black hole mergers in the occurrence of low redshift gamma-ray bursts (GRBs). The study provides evidence that these mergers could account for a significant portion of long GRBs observed at low redshifts, deviating from the previously assumed star formation rate correlation.

The researchers present both analytic and numerical arguments to support the viability of white dwarf-black hole systems as progenitors for these GRBs. They highlight the presence of kilonova signals in some long GRB light curves and an observed increase in the rate density of long GRBs at low redshifts. These findings suggest that compact object mergers, including white dwarf-black hole mergers, may contribute notably to the long GRB population.

Understanding the origins of GRBs is crucial for astrophysics, as it helps refine models of stellar evolution and the dynamics of compact objects. This research could lead to a better grasp of the mechanisms behind these powerful cosmic events and their distribution across different redshifts.

For more details, the full paper can be accessed at arXiv:2408.12654.