GCN Circular 6944
Subject
GRB 071018: SARA observations
Event
Date
2007-10-19T19:28:57Z (18 years ago)
From
Adria C. Updike at Clemson U <aupdike@clemson.edu>
Adria C. Updike, Brian Donehew, Paul Jay Searcy, Ernest Garrison, and
Dieter H. Hartmann report (on behalf of the Clemson GRB Follow-Up Team):
We observed the field of GRB 071018 (GCN 6932, Krimm et al.) beginning
1.05 days after the trigger under good weather conditions. We obtained
69 minutes of R-band images at high airmass.
Upon comparison to the sources identified by Xin et al. (GCN 6936), we
find a magnitude of 20.5 � 0.15 for OT candidate #1. We note that this
is brighter than the magnitude reported by Xin et al. half a day
earlier, so this may indeed be a variable source.
We also note a source in SDSS images at the location of GCN 6936 OT
candidate #2.
At the locations of the XRT error circles (GCN 6943, Beardmore et al.),
we detect no new sources down to a limiting magnitude of 20.8 in the R
band.
Calibration to the USNO B1.0 catalog was done relative to 10 field stars.
We would like to thank Liping Xin for providing a finder chart and
additional information on their observations. We also acknowledge the
help of Kenneth Rumstay (Valdosta U).
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