GCN Circular 23834
Subject
GRB 190202A: Swift/UVOT Detection
Date
2019-02-02T13:00:54Z (5 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
Paul Kuin (UCL/MSSL) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190202A
173 s after the BAT trigger (Lien et al., GCN Circ. 23830). The source
was also observed in R (Novichonok et al., GCN Circ. 23831). A source
consistent with the XRT position (Evans et al. GCN Circ. 23832)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 11:06:00.63 = 166.50261 (deg.)
Dec (J2000) = +09:22:36.7 = 9.37687 (deg.)
with an estimated uncertainty of 0.42 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 173 299 124 16.02 +/- 0.03
v 1613 2153 78 17.94 +/- 0.18
b 1711 1903 39 18.38 +/- 0.16
u 1686 2054 58 18.20 +/- 0.17
w1 1662 2376 97 >18.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).