{
  "subject": "EP261007b: SVOM/ECLAIRs Upper Limit",
  "createdOn": 1791557037618,
  "body": "H. Yang, O. Godet (IRAP)\nreport on behalf of the SVOM team: \n\nWe performed a targeted search to the X-ray transient EP261007b, detected by EP-WXT at 2026-10-07T15:05:16 UTC (T0) (EP team, GCN 45847), with the SVOM/ECLAIRs event-by-event data downloaded through the X-band ground station. \n\nAt T0, the transient position was within the ECLAIRs field of view. No statistically significant signal was identified in the [T0 - 3000 s, T0 + 1000 s] interval by the ECLAIRs offline trigger. \n\nFor the interval from T0 to T0 + 16 s, we derive a 3-sigma upper limit of 1.2e-8 erg/cm^2/s in the 4-120 keV energy band, assuming a power-law spectrum with a photon index of -1.9, as measured by EP-FXT for the uncatalogued source (GCN 45872). Alternatively, assuming a “soft” spectral template (a Band function with Epeak = 25 keV, alpha = -1.5, beta = -3.0), we derive a 3-sigma upper limit of 1.1e-8 erg/cm^2/s in the 4-120 keV energy band. We note that the EP/WXT flux of 7.9e-11 erg/cm^2/s in the 0.5-4 keV (GCN 45872) is more than two orders of magnitude lower than our 3-sigma upper limit. \n\nThe Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. ECLAIRs was developed jointly by APC, CEA, CNES, and IRAP.\n\nThe SVOM/ECLAIRs point of contact for this event is : Hui Yang (hui.yang@cnrs.fr) ",
  "circularId": 45876,
  "submitter": "SVOM_group <svomgroup@bao.ac.cn>",
  "eventType": [
    "X-ray Transient"
  ],
  "eventId": "EP261007b",
  "submittedHow": "web",
  "format": "text/plain"
}