GBT22A-139

Monitoring the active repeater FRB 190520

Abstract

FRB190520 is a highly active repeater discovered by FAST. Its characteristics, including host DM, burst rate, and polarization, are similar to (or more extreme than) those of FRB 121102. We are currently monitoring FRB 190520 fortnightly with FAST (1.0 to 1.5 GHz) and Parkes (0.8 to 4 GHz). Its RM has signs of rapid time evolution, seemingly at a higher rate than that of the decreasing RM of FRB 121102. These characteristics suggest that it is in an extreme magneto-ionic environment and challenge some FRB models. The percentage of linear polarization of FRB 190520 is observed to drop precipitously with decreasing frequencies. We thus propose GBT C-band (4-8 GHz) or X-band (8-10 GHz) regular monitoring of FRB 190520 to study its RM evolution as well as its frequency-dependent linear polarization, wideband emission properties, fluence distribution, and search for periodic activities. The proposed GBT observations will provide rare and valuable information on the active repeater and its environment, thus shed critical lights into the origin of FRBs.

Investigators

Name	Institution
Ryan Lynch	Green Bank Observatory
Vishal Gajjar	California at Berkeley, University of
Di Li	National Astronomical Observatories, CAS; Space Science Institute
Yongkun Zhang	National Astronomical Observatories, CAS
Chenhui Niu	National Astronomical Observatories, CAS
Pei Wang	National Astronomical Observatories, CAS
Shi Dai *	Commonwealth Scientific and Industrial Research Organisation
Steve Croft	California at Berkeley, University of
Yi Feng	National Astronomical Observatories, CAS

* indicates the PI