{
  "submittedHow": "web",
  "submitter": "SVOM_group <svomgroup@bao.ac.cn>",
  "eventId": "GRB 250419A",
  "body": "GRB 250419A: SVOM/C-GFT optical observations\n\nChao WU (NAOC), Zhe Kang (CHO), Liping Xin(NAOC), Xuhui Han(NAOC), Pinpin Zhang (NAOC), Xiaomeng Lu (NAOC), Zhenwei Li (CHO), You Lv (CHO), Ruosong Zhang (NAOC), Yujie Xiao(NAOC), Yulei, Qiu(NAOC), Jing Wang (NAOC), Jinsong Deng(NAOC), Lei Huang(NAOC), Jianyan Wei (NAOC), B.-T. Wang (YNAO, CAS), Y.H. Cheng (SWIFAR,YNU) report on behalf of the SVOM/C-GFT team:\n\nWe observed the field of GRB 250419A detected by SVOM/ECLAIRs (sb25041901, Wang et al., GCN 40168) with C-GFT. Our observations were started on 2025-04-19T13:08:53 UTC, ~10.66 hr after the trigger. \n\nThe optical counterpart (reported by Ocelotl López et al. GCN 40169, Xin et al. GCN 40170, Zheng et al. GCN 40171, Kumar et al. GCN 40172, Lipunov et al. GCN 40179, Odeh et al. GCN circ. 40180, Perley and Bochenek GCN circ. 40181, Pankov et al. GCN 40182, and Pérez-Fournon et al. GCN 40183, Kuin et al. GCN 40185) was detected in the stacked g, r, and i-band images. The results are,\n\n(T-T0)_mid(sec)  exptime(s)  mag  mag_err  band\n-----------------------------------------------\n46935      10x30s  19.38  0.17  r\n47723      10x30s  19.25  0.21  i\n49013      10x30s  19.98  0.22  g\n\n\nThe photometry was calibrated with nearby UCAC4 stars. Further analysis is on-going.\n\nWe thank the observation assistants Shuai Liu and Chunlei Guo at Jilin observatory for their excellent support.\n\n\nChinese Ground Follow-up Telescope of SVOM mission is located at Jilin, Changchun Observatory, National Astronomical Observatories, CAS. It has FOV of 1.28 deg x 1.28 deg with a 4k*4k CMOS detector mounted on the primary focus of 1.2-meter-aperure telescope.\n",
  "subject": "GRB 250419A: SVOM/C-GFT optical observations",
  "createdOn": 1745160546047,
  "format": "text/plain",
  "bibcode": "2025GCN.40186....1W",
  "circularId": 40186
}