TITLE:   GCN CIRCULAR
NUMBER:  27161
SUBJECT: GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
DATE:    20/02/21 05:15:46 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, X. Liu, Z.P. Zhu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of the possible X-ray afterglow by Swift/XRT 
(Burrows et al., GCN 27157) of GRB 200219C detected by Fermi/GBM and 
Fermi/LAT (GCN 27145; Dirirsa et al., GCN 27151), using the 0.6m NEXT 
telescope located at Nanshan, Xinjiang, China. Observations started at 
22:45:55 UT on 2020-02-20 (i.e., 22.8 h after the Fermi trigger) and 
10x300 s Sloan r-band frames were obtained.

No optical counterpart is detected in our stacked image at the Swift XRT 
position, down to a limiting magnitude of r~21.0.

Inspection of PanSTARRS reveals a faint, extended source within the XRT 
error circle. It's localized at coordinates: R.A. (J2000) = 17:30:02.21, 
Dec.(J2000) = +10:32:22.69, and has r = 22.70 +/- 0.15 mag. Thus is may 
be the host galaxy of the GRB, if the Swift XRT detection is the 
afterglow of the GRB.