GCN Circular 4978
Subject
GRB060418: Swift/UVOT Observations
Date
2006-04-18T20:46:46Z (19 years ago)
From
Patricia Schady at MSSL/Swift <ps@mssl.ucl.ac.uk>
P. Schady (UCL-MSSL), A. D. Falcone (PSU), report on behalf of the Swift/UVOT
team:
The Swift/UVOT began taking data on the field of GRB060418 at
2006-04-18T03:07:36, 88 s after the BAT trigger (Falcone et al., GCN 4966). The
source is observed to decay in six of the UVOT filters, but was not detected in
the UVW2 filter down to a 3-sigma limiting magnitude of UVW2 > 20.4 in a 949s
coadded image. This is consistent with the reported redshift of z=1.49 (Dupree
et al. 2006; GCN 4969). The magnitudes for the filters in which there was a
detection are as follows:
Filter T_mid(s) Exp(s) Mag
V 393 393 14.99 +/- 0.02
5996 197 18.84 +/- 0.33
B 675 10 16.22 +/- 0.13
10765 295 19.87 +/- 0.27
U 656 20 15.83 +/- 0.09
6610 197 18.55 +/- 0.20
UVW1 632 20 16.47 +/- 0.19
6405 197 19.04 +/- 0.40
UVM2 608 20 17.30 +/- 0.30
4343 197 > 19.30
White 137 10 14.32 +/- 0.03
11676 295 19.23 +/- 0.16
These magnitudes are uncorrected for the estimated Galactic
reddening of E_{B-V} = 0.224 mag (Schlegel et al. 1998).