Sub-second periodicity in a fast radio burst

Released: 27th July, 2022, Academia Sinica, Institute of Astronomy & Astrophysics (ASIAA), Taiwan

Banner Image Credit: Jingchuan Yu, Beijing Planetarium

Fast Radio Bursts (FRBs) are energetic transients in radio bands from cosmological distance with unknown astrophysical origin. In the past decade, about 600 FRBs have been published. The majority of them have been seen non-repeating, while some of them have been observed to repeat. Previously, only two repeaters show periodicities from two weeks to half a year. As FRBs show very diverse properties in observations, theorists have proposed over 50 models to decipher the puzzling phenomenon.

The CHIME/FRB collaboration reports FRB 20191221A in Nature, which is a non-repeating event but with nine or more components. Over a duration of ~3 seconds, the multi components show a periodicity of 216.8 milliseconds. FRB 20191221A favors emission models that originate from the neutron-star magnetosphere rather than outside of neutron stars. This is the first time that FRBs show sub-second periodicity. Dr. Ue-Li Pen and Dr. Hsiu-Hsien Lin from ASIAA are members of the CHIME/FRB collaboration, they participate in the observation, analysis, and data interpretation. Dr Pen initiated the CHIME experiment over a decade ago.

The top panel shows the de-dispersed dynamic spectrum of FRB 20191221A. In the middle panel, the black line shows the frequency-averaged profile, and the red line represents the fitting model. The bottom panel shows the residuals, i.e. the difference between the data and the model in the middle panel, in terms of signal-to-noise ratio. Credit: The CHIME/FRB Collaboration

This research was presented in the paper: Sub-second periodicity in a fast radio burst, in Nature, 607, p.256–259

Related Links:

Bustling Universe Radio Survey Telescope in Taiwan (BURSTT)

IAA Quarterly 2020 Fall Issue: Fast Radio Burst (FRB)

Media Contact:

Dr. Ue-Li Pen, (Tel) 02-2366-5300,

Dr. Hsiu-Hsien Lin, (Tel) 02-2366-5428,