GCN Circular 11514
Subject
GRB110102A: Swift/UVOT observations
Event
Date
2011-01-03T12:41:16Z (15 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL) and M. De Pasquale (MSSL-UCL) report on behalf
of the Swift-UVOT team
The Swift/UVOT began settled observations of the field of GRB 110102A
156 s after the BAT trigger (Oates et al., GCN Circ. 11509). The optical
afterglow is detected in the white, v, b and u filters at a refined UVO
position RA(J2000)= 245.88087 deg, DEC(J2000) = 7.61383, which is:
RA (J2000) = 16:23:31.41
Dec (J2000) = +07:36:49.8
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the enhanced XRT position (Goad et
al., GCN Circ. 11510).
The detection in u suggests a redshift of <2.5.
Preliminary magnitudes using the UVOT photometric system (Poole et al.
2008,
MNRAS, 383, 627) for single and summed exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag/3sigUL
#####################################################
wh (FC) 156 306 147 17.97 +/- 0.06
wh 868 1018 147 18.39 +/- 0.08
u (FC) 314 564 246 17.98 +/- 0.09
u 1122 1315 39 18.89 +/- 0.62
v 816 835 19 17.86 +/- 0.53
b 597 589 19 17.60 +/- 0.20
uvw1 693 6331 452 > 20.09
uvm2 668 6126 292 > 19.87
uvw2 619 7152 471 > 20.35
#####################################################
The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.08 in the direction of the burst
(Schlegel et al. 1998).