GCN Circular 37947
Subject
GRB 241026A: Swift/UVOT Upper Limits
Date
2024-10-29T21:43:50Z (a month ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
Via
Web form
M. H. Siegel (PSU) and A. Melandri (INAF-OAR)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 241026A
118 s after the BAT trigger (Melandri et al., GCN Circ. 37896).
No optical afterglow consistent with the XRT position
(Osborne et al., GCN Circ. 37904) or the optical counterparts
(Moskvitin et al., GCN Circ. 37899; Watson, GCN. Circ. 37900; Shrestha
et al., GCN Circ. 37913) 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 118 268 147 >19.9
u_FC 331 581 246 >19.8
white 118 1708 411 >21.0
v 662 1759 136 >19.8
b 586 1849 128 >20.6
u 331 1832 363 >20.2
w1 712 1808 117 >20.7
m2 686 1783 117 >20.7
w2 636 1734 136 >20.0
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.073 in the direction of the burst
(Schlegel et al. 1998).