GCN Circular 39544
Subject
GRB 250225B: VLT near-infrared afterglow confirmation
Event
Date
2025-03-01T18:56:01Z (9 months ago)
From
Yu-Han Yang at University of Rome Tor Vergata <yyang@roma2.infn.it>
Via
Web form
Yu-Han Yang (U Rome), Muskan Yadav (U Rome), Eleonora Troja (U Rome) on behalf of the ERC BHianca team:
We re-observed the field of GRB 250225B (Williams et al., GCN 39473) with the HAWKI imager on the ESO VLT UT4 (Yepun). Observations began at T+3.6 d days and were carried out at an average airmass of about 2.4 in the J filter.
In comparison to our first epoch of observations, the candidate counterpart (Schneider et al. GCN 39494, Yang et al. GCN 39495, Rayson et al. GCN 39535) appears to have substantially faded by about 1 mag. Image subtraction between the two epochs, reveals no other credible counterpart within the BAT error circle. We therefore confirm that this is the GRB afterglow.
We thank the staff at the VLT, for the rapid execution of these observations.