GCN Circular 21881
Subject
GRB 170912B: Swift/UVOT Upper Limits
Date
2017-09-14T02:44:20Z (7 years ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
S. J. LaPorte (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170912B
60 s after the BAT trigger (LaPorte et al., GCN Circ. 21864).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 21868)
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 57 207 147 >20.26
white 58 1024 332 >20.72
v 600 1074 58 >18.08
b 525 718 38 >18.76
u 269 1144 299 >19.67
uvw1 649 1124 58 >18.24
uvm2 624 1099 58 >18.12
uvw2 575 1050 58 >18.39
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 5.05 in the direction of the burst
(Schlegel et al. 1998).
[GCN OPS NOTE(14sep17): Per author's request, the typo in the Subject-line
was changed from "170712B" to "170912B".