GCN Circular 28774
Subject
GRB 201024A: Swift/UVOT Detection
Date
2020-10-25T00:02:46Z (4 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) 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 201024A
495 s after the BAT trigger (Marshall et al., GCN Circ. 28761). A source
consistent with the XRT position (Evans et al. GCN Circ. 28770) is
detected in the initial UVOT exposures.
Preliminary detections and 3-sigma upper limits using the UVOT photometric
system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early
exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 495 645 148 17.94 +/- 0.05
v 653 845 39 17.39 +/- 0.30
b 750 1348 58 18.65 +/- 0.32
u 726 1151 39 17.86 +/- 0.29
w1 702 1471 78 17.46 +/- 0.30
m2 677 2140 117 >18.4
w2 801 2091 117 >17.7
The observations show a rapid decay as reported by MASTER (Lipunov et al,
GCN Circ. No. 28762).
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).