GCN Circular 24747
Subject
GRB190604B: Swift/UVOT detection
Date
2019-06-04T20:40:46Z (5 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and K. L. Page (U Leicester) report on behalf
of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190604B
128 s after the BAT trigger (Page et al., GCN Circ. 24742). A faint
source is detected in the initial white UVOT exposure at a position
consistent with the enhanced XRT source position (Evans et al., GCN
Circ. 24746).
The preliminary detection 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 128 276 146 19.90 �� 0.24
white 618 812 39 >19.63
v 669 861 39 >17.95
b 594 787 39 >18.98
u 338 588 246 >19.71
uvw1 718 738 20 >17.44
uvw2 645 837 39 >18.09
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.15 in the direction of the
burst (Schlegel et al. 1998).