TITLE:   GCN CIRCULAR
NUMBER:  22157
SUBJECT: GRB 171123A: GMG observation limit
DATE:    17/11/24 12:55:39 GMT
FROM:    Jirong Mao at Yunnan Obs  <jirongmao_obs@ynao.ac.cn>

J. Mao, C.-J. Wang and J.-M. Bai (YNAO) report:


We observed the field of GRB 171123A (Evans et al., GCN 22148) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG) station of Yunnan Observatories. Observations began from 21:02:44 UT, about 6.8 hours after the trigger. We did not detect any source within the X-ray afterglow position error circle (Goad et al. GCN 22150), down to a limit of R~21.6 mag.