{
  "submittedHow": "web",
  "eventId": "GRB 260421B",
  "subject": "GRB 260421B: EP-FXT follow-up observation",
  "bibcode": "2026GCN.44387....1W",
  "submitter": "EP Team at NAOC/CAS <ep_ta@bao.ac.cn>",
  "body": "B. T. Wang (YNAO, CAS), J. P. Chen (SYSU), D. Y. Li, and W. D. Zhang (NAO, CAS) on behalf of the Einstein Probe (EP) team:\n\nEP-FXT performed a follow-up observation of the SVOM/ECLAIRs-detected burst GRB 260421B (SVOM/sb26042105; Zhao et al., GCN 44362), also triggered by Fermi-GBM (Fermi GBM team, GCN 44360; Preis & Greiner, GCN 44361; Mukherjee et al., GCN 44382), starting at 2026-04-21T06:08:31UTC, approximately 1.9 hours after the SVOM trigger, with a total exposure time of 5994 s. One uncataloged source is detected within the ECLAIRs error circle, which is spatially consistent with the optical counterpart (He et al., GCN 44363; Sanchez-Alvarez, GCN 44364; Turpin et al., GCN 44365; Wu et al., GCN 44366, Li et al., GCN 44377; Pérez-Fournon et al., GCN 44383) at a redshift of z=2.115 (Schneider et al., GCN 44368). Preliminary analysis on this source is automatically conducted, and the details are listed as follows. \n\nEPF_J124000.4-174426\nRA (J2000): 190.0018\nDec (J2000): -17.74055\nFlux: 1.26e-11 erg/s/cm2 (observed, 0.5-10 keV)\nFlux_err: 6.27e-13 erg/s/cm2 (1 sigma)\n\nLaunched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics).",
  "format": "text/plain",
  "circularId": 44387,
  "createdOn": 1776825761802
}