GCN Circular 19764
Subject
GRB 160804A: Swift/UVOT Detection
Date
2016-08-04T11:40:54Z (8 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and F. E. Marshall (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160804A 82
s after the BAT trigger (Marshall et al., GCN Circ. 19761).
A fading source consistent with the XRT position (Osborne et al. GCN
Circ. 19762) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 14:46:31.14 = 221.62976 (deg.)
Dec (J2000) = +09:59:56.7 = 9.99908 (deg.)
with an estimated uncertainty of 0.44 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT
photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for
the early exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 82 232 147 18.56 �� 0.06
white 794 944 148 19.66 �� 0.12
v 570 6762 373 >19.9
b 496 6227 432 20.4 �� 0.24
u 240 490 246 19.53 �� 0.20
w1 4182 4382 197 18.90 �� 0.25
m2 1000 5612 216 >18.7
w2 546 6637 432 >19.5
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.03 in the direction of the
burst (Schlegel et al. 1998).