GCN Circular 10134
Subject
GRB 091104: Swift/UVOT Upper Limits
Date
2009-11-04T17:13:20Z (14 years ago)
From
Peter Curran at MSSL <pac@mssl.ucl.ac.uk>
P.A. Curran (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 091104 139s
after the BAT trigger (Curran et al., GCN 10130). No optical afterglow
consistent with the enhanched XRT position (Osborne et al., GCN 10131) is
detected in the initial UVOT exposures. Preliminary 3-sigma upper limits
using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for
the finding charts (FC) and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
-------------------------------------------------------
white 139 289 147 >20.56 (FC)
u 297 547 246 >19.69 (FC)
white 139 993 301 >20.84
v 628 6155 87 >18.53
b 553 746 39 >18.88
u 297 721 265 >19.74
w1 677 870 39 >18.45
m2 652 845 39 >18.26
w2 776 4636 151 >19.71
The values quoted above are not corrected for the Galactic extinction due
to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel
et al. 1998).