GCN Circular 45207
Subject
GRB 260718A: SVOM/ECLAIRs refined analysis
Event
Date
2026-07-24T16:33:19Z (2 days ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
M. Brunet, O. Godet (IRAP), R. Hamburg (USRA), W. Zhang (PMO), Y. Ma (NAOC),
report on behalf of the SVOM/ECLAIRs team
Using the event-by-event data downloaded through the X-band ground station, we report further analysis of SVOM/ECLAIRs observations of GRB 260718A (SVOM burst-id sb26071802 – GCN 45177, trigger time T0 = 2026-07-18T11:16:34 UTC), which was also detected by Fermi/GBM (GCN 45181).
The burst that triggered ECLAIRs onboard shows a single peak lightcurve. The burst duration is T90 = 17.4 -2.0/+4.1 s in the 4-120 keV energy band.
The time-averaged spectrum from T0-2.15 s s to T0+15.0 s in the 5-120 keV energy range is best fitted by a powerlaw model with alpha = -1.95 +/- 0.05. With this model, the 4-120 keV fluence is (8.4 +/- 0.4)e-7 erg/cm^2 and the 4-120 keV photon flux is (2.16 ± 0.06) ph/cm^2/s.
All the quoted errors are at the 68% confidence level.
The 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.
The SVOM/ECLAIRs point of contact for this burst is: M. Brunet (IRAP) (marius.brunet at utoulouse.fr).