GCN Circular 16837
Subject
GRB 140919A: Swift/UVOT Detection
Event
Date
2014-09-20T11:53:48Z (11 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (IAA-CSIC/UCL-MSSL) and M.E. Gropp (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 140919A
3125 s after the BAT trigger (Gropp et al., GCN Circ. 16831).
A fading source consistent with the optical and enhanced XRT position
(Schmidl et al. GCN Circ. 16836; Beardmore et al., GCN Circ 16834)
is detected in the initial UVOT exposures. Initial identification
was complicated by the presence of a point source in the
DSS close to the optical position. Photometry is therefore also
complicated by the presence of this point source.
Preliminary detections 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) 3125 3275 147 16.62 +/- 0.05
white 45180 45480 295 19.40 +/- 0.11
v 4848 5047 197 17.33 +/- 0.10
b 8834 9134 295 18.34 +/- 0.09
u 5462 5613 148 16.86 +/- 0.07
w1 5258 5458 197 16.98 +/- 0.09
m2 5052 5252 197 17.12 +/- 0.11
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.09 in the direction of the burst
(Schlegel et al. 1998).