Fast radio bursts linked to neutron star mergers

Scientists at the University of Western Australia and the University of Nevada ( USA ) have obtained evidence of a connection between mysterious bursts of radio emission, called fast radio bursts (FRB), and the merger of neutron stars. The results of the study are published in the journal Nature Astronomy .

Astronomers have reported a potential link between the gravitational signal GW190425, resulting from the collision of two neutron stars, and the bright non-repeating radio burst 20190425A. The source of the FRB is located within the localized area of ​​the sky where the gravitational waves came from. The radio burst was seen 2.5 hours after the gravitational signal was recorded, and has a measure of dispersion corresponding to the distance obtained from the estimation of the gravitational wave parameters.

Since the probability that both events are unrelated is very small, the observations are consistent with the scenario that the merger of binary neutron stars left behind a supermassive, highly magnetized compact object. This remnant then collapsed to form a black hole, as a result of the loss of angular momentum due to the decrease in rotational speed, and produced the FRB.

Fast radio bursts occur within a few milliseconds and are accompanied by the release into outer space of a huge amount of energy – such as the Sun emits for several tens of thousands of years. Researchers attribute this phenomenon, which can be either single or repetitive, to supernova explosions, neutron star collisions, active black holes or magnetars, but the exact nature of the phenomenon is still unclear.