GCN Circular 22262
Subject
GRB 171216A: Swift/UVOT Upper Limits
Date
2017-12-19T14:12:09Z (6 years ago)
From
Frank Marshall at Swift/UVOT <marshall@milkyway.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 171216A
124 s after the BAT trigger (Marshall et al., GCN Circ. 22256).
No optical afterglow consistent with the XRT position
(Goad et al., GCN Circ. 22257)
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 124 274 147 >21.3
u_FC 282 532 246 >18.4
v 613 17562 371 >17.8
b 539 6997 359 >19.8
u 282 6886 678 >18.6
w1 662 6681 452 >19.3
m2 637 6476 274 >19.3
w2 588 12734 720 >20.1
These preliminary results may be affected by the presence of
a bright source about 10" from the XRT position.
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.26 in the direction of the burst
(Schlegel et al. 1998).