GCN Circular 35308
Subject
GRB231205B: Swift/UVOT Upper Limits
Date
2023-12-08T17:38:53Z (a year ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
Via
Web form
M. H. Siegel (PSU) and P. A. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 231205B
216 s after the BAT trigger (Evans et al., GCN Circ. 35269).
No optical afterglow consistent with the XRT position
(Osborne et al. 35275) 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 237 387 147 >21.3
white 237 536 167 >21.3
v 216 414 33 >18.6
b 492 512 19 >19.6
u 468 487 19 >18.2
w1 443 463 19 >19.3
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.204 in the direction of the burst
(Schlegel et al. 1998).