{
  "createdOn": 1790090587780,
  "submittedHow": "web",
  "subject": "GRB 260918A: SVOM/ECLAIRs refined analysis",
  "format": "text/plain",
  "body": "M. Brunet, H. Yang, O.Godet (IRAP), Yun Wang (UCB; PMO), Yehao Cheng(YNU)\nreport on behalf of the SVOM/ECLAIRs team\n\nUsing the event-by-event data downloaded through the X-band ground station, we report further analysis of SVOM/ECLAIRs observations of GRB 260918A (SVOM burst-id sb26091801 – GCN 45619, trigger time T0 = 2026-09-18T03:47:56 UTC), which was also detected as a subthreshold by Fermi/GBM (GCN 45639). \n\nThe burst that triggered ECLAIRs onboard shows a multiple peak lightcurve. The burst duration is T90 = 82 +28/-5s  in the 4-120 keV energy band.\n\nThe refined burst localization is RA, Dec = 354.725, -8.909 degrees (J2000) \n\nRA (J2000) = 23h38m54.0s\nDec (J2000) = -08d54m32.4s \n\nwith a 90% C.L. radius of 8.73 arcmin (including systematic error of 2 arcmin added in quadrature).\n\nThe time-averaged spectrum from T0-34 s to T0+36 s in the 5-120 keV energy range is best fitted by a powerlaw, model with alpha = -1.26 +0.12/-0.11. With this model, the 4-120 keV fluence is  (8.9 +/-0.9)e-7 erg/cm^2 and the 4-120 keV photon flux is 0.29 +/- 0.3 ph/cm^2/s. \n\nAll the quoted errors are at the 68% confidence level.\n\nThe Space-based multi-band astronomical 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 CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC.\n\nThe SVOM/ECLAIRs point of contact for this burst is: Marius Brunet (IRAP) (marius.brunet at utoulouse.fr)\n",
  "circularId": 45692,
  "eventId": "GRB 260918A",
  "eventType": [
    "GRB",
    "X-ray Transient"
  ],
  "submitter": "SVOM_group <svomgroup@bao.ac.cn>"
}