GCN Circular 31885
Subject
GRB 220412A: Swift/UVOT Upper Limits
Event
Date
2022-04-12T16:20:20Z (4 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. Breeveld (UCL-MSSL) and N. Klingler (GSFC/UMBC/CRESSTII) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220412A 127 s after the BAT trigger
(Klingler et al., GCN Circ. 31881).
No optical afterglow consistent with the RATIR position (Watson et al., GCN Circ. 31882) 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) exposures and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 127 276 147 >20.5
u_FC 285 479 191 >19.6
white 566 758 34 >19.7
b 542 734 34 >18.97
v 616 1059 53 >18.18
uvw1 665 857 34 >18.25
uvw2 592 1039 58 >18.64
uvm2 813 833 20 >17.37
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of
E(B-V) = 0.0373 in the direction of the burst (Schlegel et al. 1998).