Fast Radio Bursts and their Possible Neutron Star Origins

TL;DR

Fast Radio Bursts are millisecond extragalactic radio transients, potentially originating from unique neutron stars, with recent localization and repetition providing new insights into their origins.

Contribution

This paper reviews the FRB phenomenon, emphasizing the significance of FRB 121102's localization and repetition in understanding their possible neutron star origins.

Findings

FRB 121102 is localized to a star-forming region in its host galaxy.

FRB 121102 is the only known repeating FRB.

FRBs are likely extragalactic and associated with powerful neutron stars.

Abstract

The discovery of the `Lorimer Burst', a little over a decade ago, ignited renewed interest in searching for short-duration radio transients. This event is now considered to be the first established Fast Radio Burst (FRB), which is a class of millisecond-duration radio transients. The large dispersive delays observed in FRBs distinguish them from the individual bright pulses from Galactic pulsars, and suggests that they originate deep in extragalactic space. Amazingly, FRBs are not rare: the implied event rate ranges up to many thousands of events per sky, per day. The fact that only two dozen FRBs have been discovered to date is a consequence of the limited sensitivity and field of view of current radio telescopes. The precise localization of FRB 121102, the first and currently only FRB observed to repeat, has led to the unambiguous identification of its host galaxy and thus proven its extragalactic origin and large energy scale. It remains unclear, however, whether all FRBs are capable of repeating (many appear far less active) or whether FRB 121102 implies that there are multiple sub-classes. Regardless, the repetitive nature of FRB 121102 and its localization to within a star-forming region in the host galaxy imply that the bursts might originate from an exceptionally powerful neutron star - one necessarily quite unlike any we have observed in the Milky Way. In these proceedings, I give a very brief introduction to the FRB phenomenon and focus primarily on the insights that FRB 121102 has provided thus far.