{
  "createdOn": 1760726137465,
  "format": "text/plain",
  "eventId": "GRB 251017A",
  "bibcode": "2025GCN.42331....1F",
  "subject": "GRB 251017A: JinShan observations of the optical afterglow",
  "submittedHow": "web",
  "submitter": "syfu@nao.cas.cn",
  "body": "S.Y. Fu (HUST), L.B. He, X. Liu, J. An, S.Q. Jiang, Z.P. Zhu, D. Xu (NAOC), A.D. Zhu, L. Lei, H.Z. Wu (HUST), J.Z. Liu (XAO) report on behalf of a large collaboration:\n\nWe observed the field of Swift GRB 251017A (Gupta et al., GCN 42322) using the 100C telescope of the JinShan project, located at Altay, Xinjiang, China. Observations started at 2025-10-17 12:50:19.42 UT, i.e., 4.16 hours after the trigger, and a series of 300s frames in r and z bands were obtained.\n\nThe previously reported optical afterglow (Perez-Garcia et al., GCN 42323; Antier et al., GCN 42325; Sasada et al., GCN 42329) was clearly detected in our images with r-band magnitude r = 21.17 +- 0.06, calibrated with nearby Pan-STARRS1 DR2 catalog and without the Galactic extinction correction.\n\nWe acknowledge the excellent support from T.Q. Chen and J.F. Zhang for enabling these observations.",
  "circularId": 42331
}