{
  "eventId": "EP250404a",
  "body": "Kenta Taguchi, Keiichi Maeda (Kyoto U.), Masaomi Tanaka (Tohoku U.) report on behalf of a larger collaboration:\n\nWe observed the field of EP250404a detected by Einstein Probe (Hu et al., GCN 40051) using the Tricolor CMOS Camera and Spectrograph (TriCCS) on the 3.8-m Seimei telescope. Observations started at 15:27:48 UT on 2025-04-04  (MJD = 60769.64). We detected a counterpart at a position consistent with the source detected by Jiang et al. (GCN 40052, also reported by Perez-Garcia et al. GCN 40053, Du et al. GCN 40058, Konno et al. GCN 40063, Odeh et al. GCN 40064, He et al. GCN 40069, Pérez-Fournon et al. GCN 40071, Jelinek et al. GCN 40072, Rakotondrainibe et al. GCN 40073).\n\nPreliminary analysis gives the following magnitudes of the source:\ng = 18.20 +- 0.05\nr = 17.46 +- 0.04\ni = 17.10 +- 0.03\n",
  "submittedHow": "web",
  "submitter": "Kenta Taguchi <kentagch@kusastro.kyoto-u.ac.jp>",
  "bibcode": "2025GCN.40074....1T",
  "createdOn": 1743844193436,
  "subject": "EP250404a: Seimei/TriCCS optical counterpart detection",
  "format": "text/plain",
  "circularId": 40074
}