GCN Circular 20657
Subject
GRB 170208B: Swift/UVOT Upper Limits
Date
2017-02-10T01:47:01Z (7 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu>
M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170208B
127 s after the BAT trigger (Siegel et al., GCN Circ. 20632).
No optical afterglow consistent with the enhanced XRT position
(Goad et al. GCN Circ. 20635) or the GROND position
(Kruehler et al., GCN Circ. 20640)
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
u_FC 127 377 246 >20.7
v 432 2146 214 >19.6
b 382 2096 233 >20.3
u 127 2211 598 >21.3
w1 482 2195 214 >20.1
m2 457 2171 214 >19.9
w2 408 2122 234 >19.7
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).