Are There Multiple Populations of Fast Radio Bursts?

Abstract

The repeating FRB 121102 (the "repeater") shows repetitive bursting activities and was localized in a host galaxy at z = 0.193. On the other hand, despite dozens of hours of telescope time spent on follow-up observations, no other FRBs have been observed to repeat. Yet, it has been speculated that the repeater is the prototype of FRBs, and that other FRBs should show similar repeating patterns. Using the published data, we compare the repeater with other FRBs in the observed time interval (∆t) -flux ratio (S i /S i+1 ) plane. We find that whereas other FRBs occupy the upper (large S i /S i+1 ) and right (large ∆t) regions of the plane due to the non-detections of other bursts, some of the repeater bursts fall into the lower-left region of the plot (short interval and small flux ratio) excluded by the non-detection data of other FRBs. The trend also exists even if one only selects those bursts detectable by the Parkes radio telescope. If other FRBs were similar to the repeater, our simulations suggest that the probability that none of them have been detected to repeat with the current searches would be ∼ (10 −4 − 10 −3 ). We suggest that the repeater is not representative of the entire FRB population, and that there is strong evidence of more than one population of FRBs.

Non-detection of fast radio bursts from six gamma-ray burst remnants with possible magnetar engines

“…the arguments in favor of a magnetar engine are for some reasons unjustified); 2) Maybe some of the young magnetars formed the remnants are supramassive and have collapsed to black holes when our observations started; 3) The supernova ejecta may not yet become transparent to free-free emission at the observing frequency showed that the timescales for free-free transparency of the ejecta can vary from decades to up to a 100 years); 4) The synchrotron self-absorption by a flare-powered nebula may dominate the radiative processes; 5) FRB 121102 bursts are sporadic, and there are quiescent period (e.g. Price et al 2018); 6) FRB 121102 source is abnormally active compared with most young magnetars, as have been also suggested in previous studies (Palaniswamy et al 2018;Caleb et al 2019).…”

“…FRB 121102 was localized in a host galaxy with a redshift z = 0.19273(8) (Tendulkar et al 2017), confirming the cosmological origin of FRBs. Whether or not all FRBs are repeating sources is subject to debate (Palaniswamy et al 2018;Caleb et al 2019). In the literature, the FRB progenitor models can be grouped E-mail: sarah.spolaor@mail.wvu.edu † E-mail: kjlee@pku.edu.cn ‡ E-mail: zhang@physics.unlv.edu into two categories: the non-catastrophic models (related to repeating FRBs) such as giant magnetar flares (e.g.…”

Fast radio burst dispersion measures and rotation measures and the origin of intergalactic magnetic fields

“…We show how these likelihood functions can be used for parameter inference. This framework can help to infer the origin of FRBs as well as the origin of extragalactic magnetic fields (Caleb et al 2018;Palaniswamy et al 2018;Katz 2018).…”

“…Still, very little is known about the population and origin of FRBs (e. g. Katz 2018;Caleb et al 2018;Palaniswamy et al 2018;Caleb et al 2019;James 2019). To keep track of all the different models, they are collected in the living theory catalogue of FRBs (Platts et al 2018).…”

Fast Radio Bursts from Interacting Binary Neutron Star Systems

“…FRB 121102 is abnormally active, e.g. Palaniswamy et al 2018;Caleb et al 2019) or some interacting systems cannot produce FRBs because of their unfavorable pulsar parameters.…”