Search for persistent radio emission towards selected localised Fast Radio Burst positions using the MeerKAT Telescope

TL;DR

This study searches for persistent radio sources associated with localized Fast Radio Bursts using MeerKAT, finding two candidates and one non-detection, which helps understand FRB environments and progenitors.

Contribution

First systematic search for PRSs at FRB locations with MeerKAT, identifying candidate sources and setting upper limits, advancing knowledge of FRB local environments.

Findings

Two candidate PRSs detected, one non-detection.

Host galaxy associations for two FRBs.

Upper limits established for non-detected source.

Abstract

Fast Radio Bursts (FRBs) are millisecond-duration radio pulses originating from cosmological distances, as indicated by their large dispersion measures. While numerous FRBs have now been localised to their host galaxies, a distinct class of compact electromagnetic counterpart, a Persistent Radio Source (PRS), has also been identified in some cases. Currently, only three, and possible a fourth repeating FRBs (FRB20121102A, FRB20190417A, FRB20190520B, and FRB20240114A) have confirmed associations with a PRS. Insight into progenitors, local environments, and the evolution of FRBs can be clarified by characterising these PRSs. In this work, we present 2 detected candidate PRSs using MeerKAT radio telescope data and one non-detection (as part of a larger study involving 25 FRB positions). Both FRB20221106 and FRB20181112 were found to have a host galaxy, and whether the detected radio continuum emission comes from the host galaxy or PRS is still an open question. High-resolution observations from a telescope such as e-MERLIN are required to resolve this question. If a compact PRS is detected, this telescope will provide the size, and investigate the flux variability and spectral shape of this compact PRS. Lastly, in the case of FRB220190102, which was observed over two epochs, no radio continuum was detected. However, a flux upper limit is provided for both epochs.