GCN Circular 20615
Subject
GRB 170205A: Swift/UVOT Detection of a Fading Afterglow
Event
Date
2017-02-06T16:33:17Z (9 years ago)
From
Sam Emery at MSSL-UCL <samuel.emery.15@ucl.ac.uk>
S.W.K. Emery (UCL-MSSL), E. Troja (NASA/GSFC/UMCP) and A.A. Breeveld (UCL-MSSL)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170205A
314 s after the BAT trigger (Troja et al., GCN Circ. 20603).
A source consistent with the XRT position
(Beardmore et al. GCN Circ. 20610) and also detected by
Guidorzi et al. GCN 20605, Butler et al. GCN 20609 and Kruehler et al. GCN 20612
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 17:28:40.69 = 262.16955 (deg.)
Dec (J2000) = -00:03:47.3 = -0.06313 (deg.)
with an estimated uncertainty of 0.43 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(FC) 314 464 147 17.52 +/- 0.04
u(FC) 520 540 19 17.30 +/- 0.22
white 4361 4561 197 20.84 +/- 0.33
v 619 17292 1101 >20.3
b 545 565 19 17.79 +/- 0.24
u 3951 12169 785 20.65 +/- 0.33
w1 496 10592 924 >20.6
m2 6287 17909 741 >20.6
w2 4567 16378 1082 >21.1
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.35 in the direction of the burst
(Schlegel et al. 1998).