[vsnet-grb-info 19986] GRB 171027A: KAIT Optical Upper Limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22073
SUBJECT: GRB 171027A: KAIT Optical Upper Limit
DATE:    17/10/30 23:39:12 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang at berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 171027A (D'Avanzo et al.,
GCN 22053) starting at 08:26:07 UT, 181 s after the burst.
Observations were performed with an automatic sequence in the
clear (roughly R), V, and I filters, and the exposure time was 20 s
per image. We do not detect the optical source (Watson et al., GCN 22057;
Butler et al., GCN 22061) in our images. The typical limiting magnitude
of our single clear image is about 19.0 calibrated to USNO B1.0.