TITLE:   GCN CIRCULAR
NUMBER:  32738
SUBJECT: GRB221009A: LCOGT Continued Observations - Optical Upper Limits
DATE:    22/10/13 16:00:24 GMT
FROM:    Robert Strausbaugh at University of Minnesota  <rstrausb@umn.edu>

R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on
behalf of a larger collaboration:

We observed the GRB 221009A/Swift J1913.1+1946 (Dichiara et al., GCN 32632)
field with the LCOGT 1-meter Sinistro instrument at the McDonald
Observatory, Texas, USA site, on October 13, from 03:34 to 04:18
(corresponding to 84.60 to 85.50 hours from the GRB trigger time) with the
SDSS g, r, and i filters.

We performed a series of 3x300s exposures in each band.  We do not detect
the optical transient at the UVOT coordinates (Dichiara et al., GCN 32632),
in any bands.

The following upper limits are calculated using the Pan-STARRS catalog as
reference:

g > 22.3
r > 21.4
i > 20.5

These magnitudes are not corrected for galactic extinction.