GCN Circular 6481
Subject
Swift/UVOT refined analysis of GRB070531
Event
Date
2007-05-31T20:28:55Z (19 years ago)
From
Massimiliano de Pasquale at MSSL-UCL <mdp@mssl.ucl.ac.uk>
M. De Pasquale (MSSL/UCL) and C. B. Markwardt (GSFC/UMD)
report, on the behalf of Swift UVOT team:
The Swift Ultraviolet/Optical telescope (UVOT) began
its White filter finding chart exposure of GRB070531
(Markwardt et al., GCN circ. 6475) 135 seconds after
the trigger. No optical afterglow is detected inside
the refined XRT error circle (Page et al., GCN circ.
6477), in the initial V and White filter exposures and
the summed exposures in all filters.
In the following table, we report the 3 sigma
upper limits for any optical afterglow .
Filter Time (s) Exp(s) 3sigma UL Mag
White 132-231 98 19.5
White 132-966 207 19.9
V 238-637 393 19.2
V 238-1111 524 19.3
B 716-726 10 18.2
U 692-4845 76 18.9
UW1 668-4803 236 19.2
UM2 643-4598 236 19.5
UW2 745-764 20 17.8
No correction has been made for the Galactic
reddening toward the burst, E(B-V)=0.38