[vsnet-grb-info 24504] GRB 191228A: UKIRT NIR upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26603
SUBJECT: GRB 191228A: UKIRT NIR upper limit
DATE:    19/12/28 07:36:11 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu at nao.cas.cn>

D. Xu, Z.P. Zhu, B.Y. Yu, H.J. Wang, L. Ge (NAOC) report:

We observed the field of GRB 191228A (Bernardini et al., GCN 26601) 
using the 3.8-m United Kingdom Infra-Red Telescope (UKIRT). Observations 
started at 04:38:02 UT on 2019-12-28 (i.e., 4.612 hr after the BAT 
trigger), and 3600 s H-band imagining was obtained in a seeing of ~1.0".

No NIR afterglow is detected in the stacked image at the XRT position 
(Bernardini et al., GCN 26601), down to a limiting magnitude of H ~ 
20.1, calibrated with nearby 2MASS stars.

We thank the great support of the UKIRT staff/observer, in particular 
Michael Pohlen and Watson Varricatt.