GCN Circular 16772
Subject
GRB 140903A: Swift/UVOT Upper Limits
Date
2014-09-04T10:35:34Z (10 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) 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 140903A 76
s after the BAT trigger (Cummings et al., GCN Circ. 16763).
No optical afterglow consistent with the XRT position (De Pasquale et
al. GCN Circ. 16767) or optical position given by Cenko et al. (GCN
Circ. 16770), is detected in the initial UVOT exposures. The analysis is
complicated by the wings of the bright star mentioned by Capone et al.
(GCN Circ. 16767), and thus the upper limits should be treated with caution.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding
chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 77 227 147 >20.01
u_FC 289 539 246 >17.4
white 77 17449 944 >21.0
v 618 29425 1322 >18.9
b 544 17228 1376 >20.0
u 289 23404 1138 >18.2
w1 1097 22967 1121 >18.4
m2 643 6613 255 >18.8
w2 5562 28728 1918 >18.6
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.03 in the direction of the
burst (Schlegel et al. 1998).