[vsnet-grb-info 11271] GRB 111215A: GMG optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12683
SUBJECT: GRB 111215A: GMG optical upper limit
DATE:    11/12/15 17:07:53 GMT
FROM:    Dong Xu at Weizmann Inst  <dong.dark at gmail.com>

D. Xu (WIS/NAOC), X.-H. Zhao (YNAO), J.-R. Mao (KASI/YNAO), J.-M. Bai
(YNAO) report:

We observed the field of GRB 111215A (Oates et al., GCN 12681) at the
2.4m Gao-Mei-Gu (GMG) telescope equipped with YFOSC. Observations
started at 14:26:44 UT (i.e., 22.6 mins after the burst) and a series
of R-band images (totally 1700s exposure) were obtained in a seeing of
~2.8".

No optical source was detected within the XRT error circle (ref., GCN
12681) to a 3sigma limit of R~22.8 mag, calibrated with nearby USNO B1
stars.

The image trigger mode of this burst and the above R-band upper limit
might indicate high-redshift. NIR follow-ups are encouraged.