GCN Circular 17201
Subject
GRB 141220A: Swift/UVOT Detection
Date
2014-12-20T16:08:45Z (9 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and J. R. Cummings (NASA/UMBC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 141220A
597 s after the BAT trigger (Cummings et al., GCN Circ. 17196).
There were also other exposures when the spacecraft attitude
was not stable.
A source consistent with the optical position
Gorosabel et al. (GCN Circ. 17197)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 13:00:15.76 = 195.06565 (deg.)
Dec (J2000) = +32:08:47.0 = 32.14639 (deg.)
with an estimated uncertainty of 0.45 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
white 597 617 19 17.30 � 0.07
v 647 839 39 17.65 � 0.16
b 573 593 20 17.58 � 0.13
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).