GCN Circular 21874
Subject
GRB 170912A: Swift/UVOT Upper-Limits
Event
Date
2017-09-12T17:07:43Z (9 years ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
GRB 170912A: Swift/UVOT Upper Limits
S. J. LaPorte (PSU) and Tohuvavohu (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170912A
122 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 21861).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 21863)
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 122 272 147 >20.9
u_FC 335 585 246 >19.4
white 122 1362 373 >21.6
v 666 1412 97 >18.8
b 591 1338 78 >19.6
u 335 1313 304 >19.2
w1 715 1461 78 >18.7
m2 690 1436 78 >20.0
w2 641 1387 97 >19.7
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.46 in the direction of the burst
(Schlegel et al. 1998).