Nature Astronomy on GW190521 as a dynamical capture of two black holes

A new paper co-authored by Gregorio Carullo, Postdoc in the Strong Group, was published on Thursday November 17, 2022 in Nature Astronomy. The paper is entitled GW190521 as a dynamical capture of two nonspinning black holes (also available in Open Access here).

The study puts forward an alternative interpretation of GW190521, the most peculiar gravitational-wave event detected by the LIGO and Virgo interferometers. According to the study, gravitational-wave data suggest this event resulted not from the usual circular inspiral (now observed for almost a hundred of events), but by a rare capture of the two black holes lying in an hyperbolic orbit.

The study might explain the puzzling value of the black hole masses, which lie in the "supernova pair instability mass gap", pointing toward a dense environment where multiple mergers can happen efficiently.