GCN Circular 23376
Subject
GRB 181023A: Swift/UVOT Upper Limits
Event
Date
2018-10-24T00:52:14Z (8 years ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
GRB 181023A: Swift/UVOT Upper Limits
S. J. LaPorte (PSU) and F. E. Marshall (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 181023A
200 s after the BAT trigger (Marshall et al., GCN Circ. 23366).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 23369)
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 200 350 147 >20.1
white 200 2078 470 >20.8
v 356 2128 194 >19.4
b 455 2054 175 >20.3
u 430 2029 175 >19.6
w1 406 2005 175 >19.6
m2 554 1803 78 >19.2
w2 679 2104 175 >19.2
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).