A bright radio burst from FRB 20200120E in a globular cluster of the nearby galaxy M81

Abstract

Fast radio bursts (FRBs) are immensely energetic millisecond-duration radio pulses . Observations indicate that nearby FRBs can be produced by both young stellar populations, as suggested by the detection of FRB 20200428 from a Galactic magnetar SGR 1935+2154, and old stellar populations, as suggested by the localization of the repeating source FRB 20200120E in a globular cluster of M81 . Nevertheless, the burst energies of FRB 20200120E are significantly smaller than those of other cosmological FRBs, even falling below the energy of the Galactic event FRB 20200428. Additionally, its burst energy distribution displays a steep power law tail at high fluences. It is unclear whether this type of source can contribute to the cosmological FRB population. Here we report the detection of a burst from FRB 20200120E in 1.1-1.7 GHz, with a fluence of approximately 31.4 Jy ms, which is more than 44 times larger than the previous detected bursts ∼ 1.4 GHz frequencies and five times more energetic than FRB 20200428 . It reaches one-third of the energy of the weakest burst from FRB 20121102A detected so far and is detectable at a distance exceeding 200Mpc. This suggests that globular clusters can host cosmological FRBs, and the currently localized FRB sample could contain FRBs from globular clusters. Together with SGR 1935+2154, these two most nearby sources support multiple progenitor sources for FRBs.