Details

Autor(en) / Beteiligte

• Li, D.
• Wang, P.
• Zhu, W. W.
• Zhang, B.
• Zhang, X. X.
• Duan, R.
• Zhang, Y. K.
• Feng, Y.
• Tang, N. Y.
• Chatterjee, S.
• Cordes, J. M.
• Cruces, M.
• Dai, S.
• Gajjar, V.
• Hobbs, G.
• Jin, C.
• Kramer, M.
• Lorimer, D. R.
• Miao, C. C.
• Niu, C. H.
• Niu, J. R.
• Pan, Z. C.
• Qian, L.
• Spitler, L.
• Werthimer, D.
• Zhang, G. Q.
• Wang, F. Y.
• Xie, X. Y.
• Yue, Y. L.
• Zhang, L.
• Zhi, Q. J.
• Zhu, Y.

Titel

A bimodal burst energy distribution of a repeating fast radio burst source

Ist Teil von

• Nature (London), 2021-10, Vol.598 (7880), p.267-271

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2021

Beschreibungen/Notizen

• The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown 1 , 2 . As the first precisely localized source, FRB 121102 (refs. 3 – 5 ) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution 6 – 8 . However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h −1 , in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 10 37 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions. For FRB 121102, 1,652 burst events are detected over 47 days, with a peak burst rate of 122 per hour, a bimodal burst rate energy distribution, and no periodicity or quasi-periodicity.