GCN Circular 25853
Subject
GRB 190926A: Swift/UVOT Upper Limits
Date
2019-09-26T20:47:53Z (5 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (U.Warwick) and A. Melandri (INAF-OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190926A
144 s after the BAT trigger (Melandri et al., GCN Circ. 25848).
No optical afterglow consistent with the enhanced XRT position
(Goad et al. GCN Circ. 25850)
is detected in the initial UVOT exposures.
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 144 294 147 >20.2
u_FC 303 553 246 >19.3
white 144 6525 580 >20.9
v 634 11670 1116 >20.0
b 559 6321 432 >20.2
u 303 6115 659 >20.0
w1 685 5910 413 >19.8
m2 659 12294 1022 >20.3
w2 610 10756 1148 >20.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.06 in the direction of the burst
(Schlegel et al. 1998).