GCN Circular 13582
Subject
GRB 120804A: Swift/UVOT Upper Limits
Date
2012-08-04T13:40:29Z (12 years ago)
From
Margaret Chester at PSU <chester@astro.psu.edu>
M. M. Chester (PSU) and A. Y. Lien (NASA/GSFC/ORAU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120804A
97 s after the BAT trigger (Lien et al., GCN Circ. 13573).
No optical afterglow consistent with the XRT position (Osborne et al.,
GCN Circ. 13577) is detected in the initial UVOT exposures.
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) exposures and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 97 247 147 >21.4
u_FC 310 560 246 >20.7
white 97 5665 453 >22.0
v 640 6077 432 >20.6
b 566 6706 243 >20.9
u 310 6692 659 >21.3
w1 689 6487 413 >20.3
m2 4646 6282 393 >21.3
w2 4237 5872 393 >21.0
The magnitudes in the table are not corrected for the Galactic
extinction
due to the reddening of E(B-V) = 0.23 in the direction of the burst
(Schlegel et al. 1998).