GCN Circular 29453
Subject
GRB 210209A: Swift/UVOT Upper Limits
Event
Date
2021-02-10T14:39:45Z (5 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and S. L. Laha (GSFC/UMBC/CRESST) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210209A 127 s after the BAT trigger
(Laha et al., GCN Circ. 29442).
No optical afterglow consistent with the XRT position (Evans et al., GCN Circ. 29443) 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 127 276 147 >20.3
u_FC 285 535 246 >19.4
white 127 952 275 >20.4
v 615 4730 236 >19.1
b 540 733 39 >18.8
u 285 5225 345 >19.8
w1 664 5140 236 >19.7
m2 639 4934 236 >19.4
w2 590 4525 236 >20.5
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of
E(B-V) = 0.286 in the direction of the burst (Schlegel et al. 1998).