TITLE:   GCN CIRCULAR
NUMBER:  3572
SUBJECT: GRB 050709: LCO40 Observations
DATE:    05/07/11 14:39:21 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

S. Bradley Cenko, Derek B. Fox (Caltech), Edo Berger (Carnegie), and
Brian Lee (Toronto) report on behalf of the Caltech-NRAO-Carnegie
collaboration:

We have have obtained two epochs of imaging of the field of GRB 050709
(GCN 3570) with the 40-inch Swope telescope at Las Campanas Observatory.
Both epochs consisted of 3 x 600 sec images in the Sloan i' filter.  The
time of the first epoch was approximately 11 July 2005 4:15 UT (~ 29.6
hours after the burst), while the second epoch was taken 6.3 hours
later.  

Image subtraction of the two epochs reveals no variables sources to a
limiting magnitude of i' < 20.3 (estimated by comparison with several
USNO-B stars in the field).