{
  "format": "text/plain",
  "submitter": "Dong Xu at NAOC/CAS <dxu@nao.cas.cn>",
  "createdOn": 1726823317825,
  "body": "S.Q. Jiang, J. An, X. Liu, S.Y. Fu, Z.P. Zhu, D. Xu (NAOC), J.Z. Liu (XAO) report on behalf of a large collaboration:\n\nWe observed the field of EP240919a detected by EP/WXT (Liang et al., GCN 37561) and likely Fermi/GBM (Liang et al., GCN 37563), using the 100cm-B telescope (100B) of the JinShan project, located at Altay, Xinjiang, China. Observations started at 15:08:25 UT on 2024-09-19, i.e., 14.71 min after the EP/FXT trigger, and a series of frames were obtained in the Sloan r- and i- bands.\n\nNo new optical source is detected within the EP/FXT error circle (Liang et al., GCN 37561), down to the following 5-sigma upper limits:\n\n|T_mid(min)|filter|U.L.(AB)|\n|47.46     |r|     20.0|\n|35.79     |i|     19.5|\n\ncalibrated with nearby PanSTARRS stars and not corrected for Galactic extinction. \n\nWe acknowledge the excellent support from X. Yao, S.W. Luo, and Z.K. Feng for enabling these observations.",
  "submittedHow": "web",
  "circularId": 37565,
  "bibcode": "2024GCN.37565....1J",
  "subject": "EP240919a: JinShan optical upper limits",
  "eventId": "EP240919a"
}