GCN Circular 10973
Subject
GRB 100724A: Swift/UVOT observations
Date
2010-07-24T15:21:51Z (14 years ago)
From
Craig Swenson at PSU/Swift <cswenson@astro.psu.edu>
C. A. Swenson (PSU) and C. B. Markwardt (CRESST/GSFC/UMD) report
on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 100724A
74s after the BAT trigger (Markwardt et al., GCN 10968). We detect a
source at the position of the detected X-ray source (Markwardt et al.,
GCN 10968) and the location reported by GROND (Olivares et al., GCN
10969). The source is clearly fading in the UVOT white filter between
the first finding chart and a later observation.
The magnitudes and 3-sigma upper limits using the UVOT photometric
system (Poole et al., 2008, MNRAS, 383, 627) for finding chart exposures
(FC) and the summed images are:
Filter T_start T_stop Exp(s) Magnitude/3-sigma upper limit
----------------------------------------------------------------------
white (FC) 92 242 147 18.46 � 0.11
white 584 775 39 > 19.71
u (FC) 304 554 246 18.54 � 0.15
u 706 726 19 18.17 � 0.37
v 74 1050 60 > 18.31
b 559 751 39 > 18.99
uvw1 682 702 19 > 17.96
uvm2 658 850 39 > 18.19
uvw2 609 1034 58 > 18.97
The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.043 mag
(Schlegel, et al., 1998, ApJS, 500, 525).