{
  "body": "M. G. Bernardini (INAF-OAB, LUPM), N. Dagoneau, D. Turpin (CEA), J.-L. Atteia, M. Brunet (IRAP), L. P. Xin (NAOC), J. X. Cao (GXU)\n\nUsing the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 250727A (SVOM burst-id sb25072701). \n\nThe burst that triggered ECLAIRs onboard (Cao et al. GCN 41176) consists of a long soft bump detected mainly below 30 keV, with a duration of T90 = (115.1 -8.2 +14.2) s in the 4-30 keV energy band. \n\nThe time-averaged spectrum from T0-10 s to T0+100 s (T0 = 2025-07-27T10:55:41.923s) in the energy range 5-50 keV is best fitted by a powerlaw model with index 2.3+/-0.4. With this model, the total 4-50 keV fluence is (1.4+/-0.1)e-7 erg/cm^2.\n\nThe spectrum can be equally fit by a blackbody model with temperature 2.4+/-0.5 keV. With this model, the total 4-50 keV fluence is (1.1+/-0.1)e-7 erg/cm^2.\n\nAll the quoted errors are at the 68% confidence level.\n\nWe note that the calibration of SVOM/ECLAIRs is undergoing thus these results are preliminary.\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: Maria Grazia Bernardini (INAF-OAB, LUPM) (maria.bernardini at inaf.it)",
  "subject": "GRB 250727A: SVOM/ECLAIRs refined analysis",
  "submittedHow": "web",
  "bibcode": "2025GCN.41193....1B",
  "createdOn": 1753776993599,
  "circularId": 41193,
  "submitter": "SVOM_group <svomgroup@bao.ac.cn>",
  "eventId": "GRB 250727A",
  "format": "text/plain"
}