GCN Circular 22320
Subject
GRB180111A: Xinglong TNT possible optical detection
Date
2018-01-11T23:20:38Z (6 years ago)
From
L.P. Xin at NAOC <xlp@nao.cas.cn>
L. P. Xin, C. Liu, J. Y. Wei, Y. L. Qiu, J. S. Deng,
J. Wang, X. H. Han, X. M. Meng and C. Wu report:
We began to observe GRB 180111A (Lien et a l., GCN22318)
with Xinglong 0.8-m TNT telescope at 2018-01-11, 14:43:34(UT),
about 93 sec the burst.
We obtained several white and R-band images.
In any single white band frame, no any new optical transient
was detected within UVOT circle and XRT circle
(Lien et a l., GCN22318, Evens et al., GCN 22319)
down to 18.5 magnitude at the mid time of 113 sec after the burst .
However, there is a marginal source in the 20*20sec coadded image
within the XRT circle (Evens et al., GCN 22319), whose position is consistent
with the location of the reported optical counterpart (Lien et a l., GCN22318).
The brightness is about 20.0+/-0.3 calibrated by the local USNO B1.0 R2 mag
at the mid time of 300 sec after the burst.
We are making further analysis for the possible low S/N detection
since there is a bright star near the GRB location.
The message may be cited.
[GCN OPS NOTE(11jan18): The latter 'A' was added to the GRB name
in the Subject-line.]