GCN Circular 12796
Subject
GRB 120102A: Swift/UVOT Detection
Date
2012-01-02T12:41:27Z (13 years ago)
From
Alice Breeveld at MSSL-UCL <aab@mssl.ucl.ac.uk>
A. A. Breeveld (MSSL-UCL) and F. E. Marshall (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120102A
121 s after the BAT trigger (Marshall et al., GCN Circ. 12794).
A fading source consistent with the XRT position (Beardmore et al., GCN
Circ. 12795) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 18:24:53.89 = 276.22456 (deg.)
Dec (J2000) = +24:42:47.1 = 24.71309 (deg.)
with an estimated uncertainty of 0.51 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT
photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the finding chart
(FC) and early exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white (FC) 121 271 147 18.10 � 0.06
white 788 1014 167 19.9 � 0.2
v 663 1239 78 18.16 � 0.31
b 589 11310 1147 >20.8
u 334 583 246 18.52 � 0.14
w1 713 6983 452 >20.2
m2 688 6778 452 >20.1
w2 639 12879 1112 >20.9
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.13 in the direction of the
burst (Schlegel et al. 1998).