[vsnet-grb-info 20256] GRB 180111A AROMA-N optical observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22352
SUBJECT: GRB 180111A AROMA-N optical observation
DATE:    18/01/16 14:15:09 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

Y. Kitaoka, T. Sakamoto (AGU)

We observed the field of GRB 180111A detected by Swift
(Lien et al. GCN circ. 22318) with the 0.3 m AROMA-N telescope
located at Aoyama Gakuin University (Sagamihara, Japan).

10 images of 60 sec exposures were taken in the R filter starting
from January 11 on 16:44:50 (UT) about 3 minutes after the trigger
and stopped on 16:56:51 (UT).  We do not detect the optical afterglow
both in the individual images and the stacked image at the location of
the optical afterglow (Lien et al. GCN circ. 22318).  The estimated
five sigma upper limit is ~16.6 mag using the USNO-B1 catalog.