GCN Circular 39762
Subject
GRB 250316A: Swift/UVOT Upper Limits
Date
2025-03-17T13:26:57Z (17 days ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
Via
Web form
M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:
Swift/UVOT observed the field of GRB250316A (GCN 39737) for a total of 3.3 ks
in the white filter from 21.8 ks to 29 ks after the Fermi trigger. We detect no optical/UV source at the position of the XRT afterglow (Beardmore et al., GCN Circ. 39758) to an upper limit of white > 22.53. The magnitude is not corrected for the Galactic extinction due to the reddening
of E(B-V) = 0.017 in the direction of the burst (Schlegel et al. 1998).