[vsnet-grb-info 19238] GRB 170318A: KAIT Optical Upper Limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20925
SUBJECT: GRB 170318A: KAIT Optical Upper Limit
DATE:    17/03/20 19:32:13 GMT
FROM:    Max Genecov at UC Berkeley  <mgenecov at berkeley.edu>

Max Genecov, WeiKang Zhang, and Alex 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 170318A (Sbarufatti, et al.,
GCN 20904) starting at 12:33:14 UT, ~23 minutes after the burst.
The target was at low elevation but rising. Observations were performed
with an automatic sequence in the clear (roughly R) and I filters, and
the exposure time was 20 s per image. We do not detect any optical
source within the XRT error circle (Evans, et al., GCN 20907).
The limiting magnitude of the co-added clear band image is ~17.6 at
a mid-time of 39.7 minutes after the burst.