GCN Circular 31320
Subject
GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
Date
2021-12-28T02:22:53Z (2 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
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 211227A (Beardmore et al. GCN Circ. 31316)
using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China.
Observations automatically started at 23:33:37 UT on 2021-12-27 (i.e.,
90.14 s after the BAT trigger), and a series of 40 s, 60 s, 90 s frames
were obtained in the Sloan r-filter.
Within the Swift/XRT error circle (Beardmore et al. GCN Circ. 31316), no
uncatalogued optical transient is detected in our stacked image down to
a limiting magnitude of r ~ 20.0 mag, calibrated with the nearby
PanSTARRS field.
However, there exists a known source at the border of the Swift/XRT
error circle at coordinates: R.A. (J2000)=08:48:35.975 and Dec (J2000)=
-02:44:06.93, which has r ~ 19.6 mag from Nanshan/NEXT, r ~ 19.40 mag
and classified as galaxy with a photo-redshift of 0.244 +/- 0.0888 from
SDSS, r ~ 19.47 mag from PanSTARRS, as well as r ~ 19.25 from Legacy
Survey. No apparent brightening of the galaxy is seen in comparison of
Nanshan/NEXT and different surveys, indicating that the contribution of
the optical counterpart of the burst is negligible if the galaxy is the
host of the burst.