{
  "submittedHow": "web",
  "submitter": "Zipei Zhu at NAOC <zpzhu@nao.cas.cn>",
  "body": "Z.P. Zhu, X. Liu, D. Xu, J. An,S.Q. Jiang, L.B. He (NAOC), S.Y. Fu, H.Z. Wu, A.D. Zhu, L. Lei (HUST), J.Z. Liu (XAO) report:\n\nWe observed the field of GRB260604C detected by Fermi-GBM (Fermi GBM team, GCN 44822) and SVOM (Gotz et al, GCN 44823), using the JinShan 100B telescope located at Altay, Xinjiang, China. Observation started at 2026-06-04T20:32:14 UT, i.e., about 13 min post-burst, and a series of r-band frames were obtained.\n\nThe previously reported optical counterpart (Lipunov et al, GCN 44827; Konno et al, GCN 44828) is detected in our first single frame with a brightness of R = 16.1 +/- 0.1, calibrated with Pan-STARRS DR2 stars in the field and not corrected for Galactic extinction.\n\nWe acknowledge the excellent support from T.Q. Chen, and J.F. Zhang for enabling these observations.",
  "editedBy": "Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Zipei Zhu at NAOC <zpzhu@nao.cas.cn>",
  "subject": "GRB 260604C: Jinshan optical observations",
  "eventId": "GRB 260604C",
  "format": "text/plain",
  "version": 2,
  "createdOn": 1780627977606,
  "circularId": 44832,
  "editedOn": 1780669872352
}