Nine New Repeating Fast Radio Burst Sources from CHIME/FRB

Abstract

We report on the discovery and analysis of bursts from nine new repeating fast radio burst (FRB) sources found using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. These sources span a dispersion measure (DM) range of 195-1380 pc cm −3 . We detect two bursts from three of the new sources, three bursts from four of the new sources, four bursts from one new source, and five bursts from one new source. We determine sky coordinates of all sources with uncertainties of ∼10′. We detect Faraday rotation measures (RMs) for two sources, with values −20(1) and −499.8(7) radm −2 , that are substantially lower than the RM derived from bursts emitted by FRB 121102. We find that the DM distribution of our events, combined with the nine other repeaters discovered by CHIME/FRB, is indistinguishable from that of thus far non-repeating CHIME/FRB events. However, as previously reported, the burst widths appear statistically significantly larger than the thus far non-repeating CHIME/FRB events, further supporting the notion of inherently different emission mechanisms and/or local environments. These results are consistent with previous work, though are now derived from 18 repeating sources discovered by CHIME/FRB during its first year of operation. We identify candidate galaxies that may contain FRB 190303.J1353+48 (DM=222.4 pc cm −3 ).

Diverse polarization angle swings from a repeating fast radio burst source

“…All the bursts have intrinsic widths of a few milliseconds with no apparent evidence of scattering (see Table 1). These features resemble those commonly seen in repeating FRBs 10,[15][16][17] . Some bursts (e.g.…”

“…Some bursts (e.g. burst 5) show a clear frequency down-drifting pattern, as also observed in some other repeating bursts 10,[16][17][18] , suggesting a common physical origin.…”

High-cadence observations and variable spin behaviour of magnetar Swift J1818.0−1607 after its outburst

“…It is interesting to note that FRBs also tend to show flat position angle swings (e.g. Fonseca et al 2020), and indeed the single pulse shown in Figure 6 or the average profiles shown in Figure 7 do resemble observed FRB pulse shapes. Given the short rotational period by magnetar-standards ( Fig.…”

The Multiwavelength Counterparts of Fast Radio Bursts

“…Five FRB sources have been directly associated with host galaxies, revealing a range of galaxy classes and source environments (Chatterjee et al 2017;Bannister et al 2019;Prochaska et al 2019;Ravi et al 2019;Marcote et al 2020). Repeat bursts have been observed from 20 FRB sources (Spitler et al 2016;CHIME/FRB Collaboration et al 2019a, 2019bKumar et al 2019;Fonseca et al 2020), indicating that at least some FRBs originate from noncatastrophic events (see also Ravi 2019). The exact FRB emission mechanism(s) and engine(s) remain elusive.…”