GCN Circular 44740
Subject
GRB 260527A / EP260527a: VLA radio detection
Event
Date
2026-05-29T16:53:30Z (21 hours ago)
From
Genevieve Schroeder at Cornell University <genevieveschroeder@u.northwestern.edu>
Via
Web form
G. Schroeder (Cornell), J. Rastinejad (UMD), W. Fong (Northwestern) report:
We observed the location of the short-duration GRB 260527A / EP260527a (Yang et al. GCN 44718, Svinkin et al. GCN 44722, Yu et al. GCN 44724) with the Karl G. Jansky Very Large Array (VLA) in A configuration under program 26A-062 (PI Schroeder) at a mid time of 2026 May 29 at 04:47 UT (1.9 days post-burst) for 0.75 hours at a mean frequency of 6 GHz.
In preliminary analysis, we detect a 3-sigma radio source with a flux density of ~50 microJy at the position:
RA(J2000) = 12:52:13.141
Dec(J2000) = +01:28:56.47
with an uncertainty of ~0.1" in each coordinate. This position is offset by ~0.4" from the optical counterpart (Aguilar-Ruiz et al. GCN 44719). At the proposed event redshift of z=0.8 (Yang et al. GCN 44736), this corresponds to a rest-frame luminosity of ~ 9e29erg/s/Hz, on the bright end of typical short-duration Gamma-ray burst radio afterglow luminosities at a similar rest-frame time (e.g., Laskar et al. 2022, Anderson et al. 2025, Belkin et al. 2026). Further observations are planned to assess the variability of the radio source and its connection to GRB 260527A and EP260527a.
We thank the VLA staff for quickly approving and executing these observations.