GCN Circular 35777
Subject
GRB 240222A: Swift/UVOT Upper Limits
Date
2024-02-22T22:34:59Z (2 months ago)
From
Samantha Oates at University of Birmingham <samantha.oates@alumni.ucl.ac.uk>
Via
email
S. R. Oates (Lancaster. U) and P. D'Avanzo (INAF-OAB) report on behalf of the
Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 240222A
98s after the BAT trigger (D'Avanzo et al., GCN Circ 35770). No optical
afterglow consistent with X-ray (D'Avanzo et al., GCN Circ. 35770) position 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 initial exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 98 1192 205 >20.9
v 642 1068 58 >18.5
b 567 1168 58 >19.5
u 311 1142 285 >20.0
uvw1 691 1118 39 >18.3
uvm2 666 861 39 >18.0
uvw2 617 1044 58 >18.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.16 in the direction of the burst
(Schlegel et al. 1998).