GCN Circular 36179
Subject
GRB 240411B: Swift/UVOT Detection
Date
2024-04-19T12:32:47Z (6 months ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
Via
email
S. J. LaPorte (PSU) and T. M. Parsotan (GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 240411B
190 s after the BAT trigger (Parsotan et al., GCN Circ. 36063). A source
consistent
with the XRT position (Goad et al., GCN Circ. 36065) and the reported
optical transient (Izzo et al. GCN 36064; Schneider et
al. GCN 36067; Ror et al. GCN 36069; Ugarte Postigo et al. GCN 36074; Aryan
et al. GCN 36077; Pankov et al. GCN 36078) 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
b 6480 6680 196 >19.84
v 7096 7295 196 >18.58
uvw2 6891 7091 196 >19.45
white 6685 6885 196 >20.54
white 198 348 147 20.08+-0.27
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.022 in the direction of the burst
(Schlegel et al. 1998).