VLA/realfast detection of burst from FRB180916.J0158+65

ATel #13664; K. Aggarwal and realfast collaboration
on 24 Apr 2020; 16:41 UT
Credential Certification: Casey Law (claw@astro.caltech.edu)

Tweet

We report the detection of a radio burst from the repeating fast radio burst (FRB) source FRB180916.J0158+65 with the Very Large Array (VLA) and the realfast commensal transient search system (Law et al 2018). The realfast commensal transient search system currently runs by default on VLA continuum observations at frequencies from 1 to 12 GHz (see http://realfast.io/ ).

On April 23 at 20:11 UTC, the VLA was pointed to the location of FRB180916.J0158+65 to run a routine test of realfast system. The observations were being done at L band (1.36 - 2 GHz) with realfast system searching visibilities sampled at a 10ms cadence. The search pipeline recorded visibilities and imaged each integration for DM from 0-1500 pc/cm3 and time widths from 10 to 80 ms. Each image with a peak S/N above 7 was saved for further analysis. The burst was detected at a S/N of 13 at a DM of 349.8 pc/cc3 with fetch astrophysical classification score of 0.99 (Agarwal et al 2019). The peak flux density of the burst was approximately 0.13 Jy over the band and its temporal width less than 10 ms. The realfast search system localized the burst in realtime to a location of RA = 1h58m00.634s, Dec = 65d43m00.6331s, which consistent with the EVN localization (Marcote et al 2020) given the VLA localization precision of 0.8".

This FRB has previously been detected at 300 MHz (Chawla et al 2020, Pilia et al 2020), 400 MHz (CHIME/FRB Collaboration 2019) and 1400 MHz (Marcote et al 2020). It was was recently found to be periodic (CHIME/FRB Collaboration 2020) with a period of 16.35 days. The burst was detected at a topocentric MJD of 58962.84120459 (at infinite frequency). This is consistent with a time at the start of a new ~4-day activity period. Follow-up observing is encouraged.

Visualizations of realfast detection