{
  "bibcode": "2025GCN.41199....1Y",
  "circularId": 41199,
  "submittedHow": "web",
  "submitter": "EP Team at NAOC/CAS <ep_ta@bao.ac.cn>",
  "format": "text/plain",
  "createdOn": 1753856115475,
  "eventId": "GRB 250727A",
  "body": "Y.-H. I. Yin (NJU), R. D. Liang, W. Yuan (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 250727A (SVOM/sb25072701) (Cao et al. GCN 41176) at 2025-07-29T10:57:54 (UTC), about 48 hours after the SVOM/ECLAIRs trigger, with an exposure time of 3878s. Three FXT candidate sources (Yin et al. GCN 41182) are not detected in this observation. The upper limits are listed as follows.\n\nSource 1: EPF_J234436.3-810410\nRA (J2000): 356.1514\nDec (J2000): -81.0694\nFlux upper limit: 8.78 x 10^-14 erg/s/cm2 (0.5-10 keV)\n\nSource 2: EPF_J234357.8-811244\nRA (J2000): 355.9909\nDec (J2000): -81.2121\nFlux upper limit: 1.03 x 10^-13 erg/s/cm2 (0.5-10 keV)\n\nSource 3: EPF_J234541.4-811245\nRA (J2000): 356.4225\nDec (J2000): -81.2124\nFlux upper limit: 6.40 x 10^-14 erg/s/cm2 (0.5-10 keV)\nNote: This source is spatially consistent with the candidate counterpart Source 1 (SWIFT J234539.1-811248) detected by Swift/XRT.\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).",
  "subject": "GRB 250727A: EP-FXT follow-up observation"
}