GCN Circular 13735
Subject
GRB 120909A: Swift/UVOT Detection
Date
2012-09-09T18:02:19Z (12 years ago)
From
Alice Breeveld at MSSL-UCL <aab@mssl.ucl.ac.uk>
A. A. Breeveld (MSSL-UCL) and S. Immler (CRESST/GSFC/UMD) report on
behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120909A
3308 s after the BAT trigger (Immler et al., GCN Circ. 13727).
A source consistent with the optical position (Sudilovsky et al. GCN
Circ. 13729), 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
white 3308 4690 344 20.75 � 0.20
v 3465 16690 1261 >20.2
b 4285 23216 937 >21.5
u 4080 22450 1848 >21.4
w1 3875 21536 1968 >21.6
m2 3670 17445 1820 >21.4
w2 4696 15776 1082 >21.6
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.09 in the direction of the
burst (Schlegel et al. 1998).