A Nearby Repeating Fast Radio Burst in the Direction of M81

Abstract

We report on the discovery of FRB 20200120E, a repeating fast radio burst (FRB) with a low dispersion measure (DM) detected by the Canadian Hydrogen Intensity Mapping Experiment FRB project. The source DM of 87.82 pc cm −3 is the lowest recorded from an FRB to date, yet it is significantly higher than the maximum expected from the Milky Way interstellar medium in this direction (∼50 pc cm −3 ). We have detected three bursts and one candidate burst from the source over the period 2020 January-November. The baseband voltage data for the event on 2020 January 20 enabled a sky localization of the source to within ;14 arcmin 2 (90% confidence). The FRB localization is close to M81, a spiral galaxy at a distance of 3.6 Mpc. The FRB appears on the outskirts of M81 (projected offset ∼20 kpc) but well inside its extended H I and thick disks. We empirically estimate the probability of a chance coincidence with M81 to be <10 −2 . However, we cannot reject a Milky Way halo origin for the FRB. Within the FRB localization region, we find several interesting cataloged M81 sources and a radio point source detected in the Very Large Array Sky Survey. We search for prompt X-ray counterparts in Swift Burst Alert Telescope and Fermi/GBM data, and, for two of the FRB 20200120E bursts, we rule out coincident SGR 1806 −20-like X-ray bursts. Due to the proximity of FRB 20200120E, future follow-up for prompt multiwavelength counterparts and subarcsecond localization could be constraining of proposed FRB models. Unified AstronomyThesaurus concepts: Radio transient sources (2008); Radio bursts (1339); Transient sources (1851); Radio pulsars (1353)

Periodic Fast Radio Bursts from Luminous X-ray Binaries

“…On the other hand, the relatively fainter bursts (∼10 37 erg s −1 ; see Figure 2) from the nearest observed repeating FRB 200120 (at ∼3.6 Mpc) can be predicted to exhibit an X-ray flux of ∼10 −13 erg s −1 cm −2 through the accretion channel. This is well below the sensitivity limit of existing X-ray telescopes, consistent with the reported X-ray upper limits from the source error region (Bhardwaj et al 2021).…”

“…Figure 2 shows the observed durations and luminosities of a large sample of FRBs, including the well-studied repeating sources FRB 121102 and FRB 180916, and the nearest extragalactic FRB 200120 (Bhardwaj et al 2021). The top axis gives the value of M • corresponding to t min (Equation (1)) for R isco ; 2R g (a rough lower limit corresponding to a rapidly spinning BH).…”

“…If most of the luminous FRBs are powered by accreting compact objects, the latter must be NSs or stellar-mass BHs accreting near or well above the Eddington rate. Here we show the observed isotropic luminosities and durations of repeating and non-repeating FRBs as filled and non-filled gray circles, including ranges for the repeating sources, FRB 121102 (square), FRB 180916 (diamond; http://www.frbcat.org;Petroff et al 2016), and FRB 200120 (star;Bhardwaj et al 2021). The top axis shows the NS/BH mass M • corresponding to the minimum FRB duration t min (Equation (1)) assuming R isco = 2R g .…”

Dynamical Formation Channels for Fast Radio Bursts in Globular Clusters

“…The recently discovered repeating FRB 20200120E (Bhardwaj et al 2021) was localized to an old (t ∼ 10 Gyr) globular cluster (GC) in M81 (Kirsten et al 2021). In a presentday GC, neutron stars (NSs)/magnetars formed in association with massive star evolution have been inactive for billions of years.…”

Sub-second periodicity in a fast radio burst

“…The polarisation analysis of FRBs 20210206A and 20210213A follows a similar procedure to that previously applied to other CHIME-detected FRBs. 21,53 In particular, an initial RM estimate is made by applying RM-synthesis 54,55 to the Stokes Q and U data of each burst. The Stokes spectrum is extracted by integrating the polarised signal over the burst duration, where time and frequency limits have been manually adjusted to optimize the RM detection.…”