A Unified Understanding of Fast Radio Bursts
Discovering fast radio bursts (FRBs) and measuring their physical properties have become the leading scientific goals of many current and future telescopes. This effort has led to a rapidly growing sample of FRBs with extremely diverse characters, in luminosity (1038 to 1045 erg/s), frequency (300 MHz to 8 GHz), duration (0.1 ms to 10 ms), polarization (from weakly polarized to 100% linear), repeating rate (many per hour to so-far non-repeaters), and distances (10 kpc to many Gpc). We study the cosmological volumetric rate density and provide evidence that these bursts all belong to the same class of transients --- most likely all repeaters. We suggest that magnetic disturbances close to the surface of a magnetar propagate to a distance of a few tens of neutron star radii where they damp and produce coherent radio emission. The coincident hard X-ray emission associated with the two pulses seen in FRB 200428 as well as the radio to X-ray flux ratio can be understood in this scenario. This model provides a unified picture for faint Galactic FRBs as well as the bright events seen at cosmological distances. If time allows, the polarization properties will also be addressed.
|Date: ||Mardi, le 29 septembre 2020|
|Lieu: ||Université McGill|
| ||Zoom: URL: https://mcgill.zoom.us/j/92574500164?pwd=WTVWU3hPQ0NZZFFhT25aNERTOTlMZz09 Meeting ID: 925 7450 0164 Passcode: 230063|