S.Y. Fu (NAOC), Z.P. Zhu (NAOC,HUST), X. Liu, S.Q. Jiang, D. Xu (NAOC),
X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:
We observed the field of GRB 220117A detected by Swift (Melandri et al.,
GCN 31466) using the NEXT-0.6m telescope located at Nanshan, Xinjiang,
China. Observations automatically started at 16:21:57 UT on 2022-01-17
(i.e., 186 s after the BAT trigger), and a series of 40 s, 60 s, 90 s,
200 s frames were obtained in the Sloan r- and z- filters.
No uncatalogued optical transient is detected in our stacked images at
the Swift-XRT position (GCN 31466), down to limiting magnitudes of
r~19.6 and z~18.7, calibrated with the nearby PanSTARRS field.
Nevertheless, we note that from PanSTARRS there exists a source at the
border of the Swift-XRT error circle at coordinates R.A. (J2000) =
6:06:17.32 and Dec. (J2000) = -28:26:13.07, which has magnitudes of g
~21.51, r~21.05, i~20.99, and z~21.02, rasing the possibility as the
host galaxy of the GRB. This sky area is not covered by SDSS and Legacy
Survey. SkyMapper covered the sky area with upper limits of r~19.0 and
z~19.0, comparable to the NEXT's level. It is thus unclear if the
PanSTARRS source is related to the GRB or not.