[vsnet-grb-info 25005] GRB 200216B: Nanshan/NEXT early optical upper limit and possible host galaxy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27104
SUBJECT: GRB 200216B: Nanshan/NEXT early optical upper limit and possible host galaxy
DATE:    20/02/16 15:09:41 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu at nao.cas.cn>

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

We observed the field of GRB 200216B (D'Avanzo et al., GCN 27102) using 
the NEXT 0.6m optical telescope located at Nanshan, Xinjiang, China. 
Observations automatically started at 13:33:46 UT on 2002-02-16, i.e., 
73 s after the BAT trigger. We obtained 3x40 s, 4x60 s, 3x90 s and 
onging 200 s frames in the Sloan r-filter. The altitude for the GRB and 
the weather has been improving.

No optical afterglow is detected in our images at the XRT position 
(D'Avanzo et al., GCN 27102) down to a limiting magnitude of r~20.0.

Meanwhile, we note that there exists a very marginally detected blob 
(thus noise fluctuation not ruled out yet), extended and being 
positionally consistent with the XRT position both in PanSTAR r-band 
field, centred at coordinates: R.A. (J2000) = 10:41:44.23, Dec. (J2000) 
= +19:28:33.18. The source would be of r~23 in depth, and might be the 
host galaxy of the GRB. Deep imaging would identify the nature of the blob.