GCN Circular 17787
Subject
GRB 150428B: Swift/UVOT Upper Limits
Date
2015-04-29T13:20:58Z (9 years ago)
From
Margaret Chester at PSU <chester@swift.psu.edu>
M. M. Chester (PSU) and K. L. Page (U Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150428B 117
s after the BAT trigger (Page et al., GCN Circ. 17766). No optical
afterglow consistent with the enhanced XRT position (Beardmore et al., GCN
Circ. 17773) 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) exposures and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) UL (3-sigma)
white_FC 117 267 146 >20.9
u_FC 329 579 246 >20.1
white 117 5414 588 >21.6
v 659 5825 313 >19.6
b 584 6598 445 >20.8
u 329 6440 717 >20.8
w1 708 6235 293 >20.0
m2 683 6030 294 >19.9
w2 634 5620 313 >20.2
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.40 in the direction of the burst
(Schlegel et al. 1998).