{
  "bibcode": "2021GCN.30504....1F",
  "body": "S.Y. Fu (NAOC), Z.P. Zhu (NAOC, HUST), X. Liu, D. Xu (NAOC), X. Gao \n(Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:\n\nWe continued to observe the field of GRB 210722A (D'Avanzo et al., GCN \n30475) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, \nChina. We obtained 15x200 s frames in the Sloan r-band, starting at \n20:41:20 UT on 2021-07-24, i.e., 1.99 days after the burst.\n\nThe previously reported optical afterglow (e.g., D'Avanzo et al., GCN \n30475; Zhu et al., GCN 30476) is not detected in our stacked image, down \nto a limiting magnitude of r~21.0, calibrated with the nearby PanSTARRS \nfield.",
  "circularId": 30504,
  "createdOn": 1627199789000,
  "email": "dxu@nao.cas.cn",
  "subject": "GRB 210722A: Nanshan/NEXT further optical observations",
  "submitter": "Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>",
  "eventId": "GRB 210722A"
}