GCN Circular 21294
Subject
GRB 170705A: Swift/UVOT Detection
Event
Date
2017-07-05T15:08:53Z (9 years ago)
From
Sam Emery at MSSL-UCL <samuel.emery.15@ucl.ac.uk>
S.W.K. Emery (UCL-MSSL) and R. L. C. Starling (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170705A
82 s after the BAT trigger (Starling et al., GCN Circ. 21289).
We detect a fading source consistent with the XRT position
(Goad et al., GCN Circ. 21290) and the MASTER (Lipunov et al., GCN Circ. 21291)
and RATIR (Butler et al., GCN Circ. 21293) detections in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 12:46:48.97 = 191.70404 (deg.)
Dec (J2000) = +18:18:26.4 = 18.30733 (deg.)
with an estimated uncertainty of 0.45 arc sec. (radius, 90% confidence).
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 82 231 147 18.55 +/- 0.06
white 573 1020 186 19.23 +/- 0.11
u 294 543 246 19.43 +/- 0.19
v 623 1070 58 >18.3
b 549 741 39 18.92 +/- 0.26
uvw1 672 692 19 >18.1
uvm2 4617 12950 996 >20.7
uvw2 5644 11420 1137 >21.0
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).