GBT22B-030

Monitoring the active repeater FRB 20190520B

Abstract

FRB20190520B 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 20121102A. 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 20190520B 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 20190520B to study its RM evolution as well as its magnetic field geometric configuration, frequency-dependent linear polarization, 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
Shen Wang	National Astronomical Observatories, CAS
Vishal Gajjar	California at Berkeley, University of
Yuan-Pei Yang	Yunnan University
Steve Croft	California at Berkeley, University of
Di Li	National Astronomical Observatories, CAS; Space Science Institute
Yi Feng	National Astronomical Observatories, CAS
Pei Wang	National Astronomical Observatories, CAS
Shi Dai *	Commonwealth Scientific and Industrial Research Organisation
Yongkun Zhang	National Astronomical Observatories, CAS
Chenhui Niu	National Astronomical Observatories, CAS

* indicates the PI