Presentation Archive

Fast Radio Burst Radiation Mechanism and Cosmology

Pawan Kumar (UT Austin)

February 25, 2021

Abstract: The detection of a Fast radio burst (FRB) in 2007 was a major unexpected discovery in astronomy in decades. Hunting for FRBs and measuring their physical properties have become one of the leading scientific goals in astronomy; CHIME – the Canadian project for which people at CITA have played very important role – has increasingly become the dominant player in this new field. It is well established that many FRBs are located at a distance of several billion lightyears, and therefore they are the brightest known transients in the universe in the radio band. Using very general arguments, I will show that the radio emission is coherent, the magnetic field strength associated with the source of these events should be 10^{14}Gauss or more. Recently, an FRB was discovered in the Galaxy and it confirmed that at least some FRBs are associated with magnetars. I will describe my recent work regarding how the FRB radiation is produced and provide a unified picture for the weak Galactic FRB as well as the bright bursts seen at cosmological distances. I will discuss how FRBs can be used as a probe of the baryon distribution in the universe and for investigating the epoch of reionization.