GCN Circular 35069
Subject
GRB 231111A: Swift/UVOT Detection
Date
2023-11-17T00:10:52Z (a year ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
Via
email
GRB 231111A: Swift/UVOT Detection
S. J. LaPorte (PSU) and A. Melandri (INAF-OAR)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 231111A
165 s after the BAT trigger (Melandri et al., GCN Circ. 34981).
A source consistent with the XRT position
(Evans et al., GCN Circ. 34991)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 19:20:45.25 = 290.18856 (deg.)
Dec (J2000) = +52:26:10.5 = 52.43624 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).
Preliminary detections 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 26598 27505 885 >20.41
uvm2 34150 34575 418 >20.05
u 180 418 234 16.52
v 33541 34144 590 >19.85
uvw1 38947 39736 776 >20.24
uvw2 27512 85141 1176 >20.65
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.117 in the direction of the burst
(Schlegel et al. 1998).