Detection and localisation of the highly active FRB 20240114A with MeerKAT

ABSTRACT We report observations of the highly active FRB 20240114A with MeerKAT using the ultra-high frequency (UHF; 544\!-\!1088 MHz) and L band (856\!-\!1712 MHz) receivers. A total of 62 bursts were detected in coherent tied-array beams using the MeerTRAP real-time transient detection pipeline. We measure a structure-optimizing dispersion measure of 527. 65 0. 01\, pc\, cm^-3 using the brightest burst in the sample. We find the bursts of FRB 20240114A are generally detected in part of the broad-band of MeerKAT, 40~{\ per\ cent} in the UHF and 30~{\ per\ cent} in the L band, indicating the band limited nature. We analyse the fluence distribution of the 44 bursts detected at UHF, constraining the fluence completeness limit to 1 Jy ms, above which the cumulative burst rate follows a power law R (F) (F/1\, Jy\, ms) ^ with =-1. 8 0. 2. Using channelized telescope data captured in our transient buffer we localize FRB 20240114A in the image domain to RA = 21h27m39. 86s, Dec. = +04d19m45. 01s with an uncertainty of 1. 4 arcsec. This localization allows us to confidently identify the host galaxy of FRB 20240114A. Also using the transient buffer data, we perform a polarimetric study and demonstrate that most of the bursts have 100~{\ per\ cent} linear polarization fractions and up to 20~{\ per\ cent} circular polarization fractions. Finally, we predict the flux density of a potential persistent radio source (PRS) associated with FRB 20240114A is 0. 6\!-\!60\, Jy based on the simple relation between the luminosity of the PRS and the rotation measure arising from the FRB local environment.