GCN Circular 27244
Subject
GRB 200227A: Swift/UVOT Upper Limits
Date
2020-02-27T21:16:21Z (4 years ago)
From
Samantha Oates at MSSL <samantha.oates@alumni.ucl.ac.uk>
S. R. Oates (U. Birmingham) and S. Laha (GSFC/UMBC/CRESST)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 200227A
93 s after the BAT trigger (Laha et al., GCN Circ. 27234).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 27243)
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 93 243 147 >20.3
u_FC 305 555 246 >19.7
white 93 1185 353 >20.8
v 634 1235 78 >18.3
b 560 1160 58 >19.2
u 305 1135 285 >19.8
w1 685 1284 58 >18.4
m2 659 1259 78 >18.4
w2 610 1210 78 >18.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the significant reddening of E(B-V) = 0.28 in the direction of the burst
(Schlegel et al. 1998).