GCN Circular 14017
Subject
GRB 121128A: Swift/UVOT Detection
Date
2012-11-28T22:58:50Z (12 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 121128A
85 s after the BAT trigger (Oates et al., GCN Circ. 14007). A source consistent
with the XRT position (Osborne et al., GCN Circ. 14015) is detected in the initial
white, v, b and u exposures only. The non-detection in the UV filters is consistent
with the redshift of z=2.2 reported by Gemini North (Tanvir et al., GCN Circ. 14009)
The preliminary UVOT position is:
RA (J2000) = 20:02:24.00 = 300.60000 (deg.)
Dec (J2000) = +54:17:59.1 = 54.29974 (deg.)
with an estimated uncertainty of 0.50 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 early exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 85 235 147 16.19 +/- 0.03
v 629 649 19 17.00 +/- 0.23
b 554 573 20 17.51 +/- 0.17
u 298 547 246 17.33 +/- 0.06
w1 679 2173 175 >19.6
m2 654 2496 214 >19.6
w2 605 2447 214 >20.0
The magnitudes in the table are not corrected for the significant Galactic extinction
due to the reddening of E(B-V) = 0.31 in the direction of the burst
(Schlegel et al. 1998).