GCN Circular 41842
Subject
GRB 250910A: SVOM/ECLAIRs refined analysis
Event
Date
2025-09-16T16:03:05Z (7 days ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
Baptiste Hubert, Nicolas Dagoneau, Stéphane Schanne (CEA), Jean-Luc Atteia (IRAP), Frédéric Piron (LUPM), Yinuo Ma, Donghua Zhao, Wenjin Xie (NAOC)
Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 250910A (SVOM burst-id sb25091001).
The burst that triggered ECLAIRs (GCN 41769) consists of a broad structure with a duration of T90 = 22 -2/+3 s in the 4-20 keV energy band.
The time-averaged spectrum from T0-15.5 s to T0+6.7 s (T0 = 2025-09-10T03:16:30) in the energy range 4-120 keV is best fitted by a power-law model with photon index 1.7 +/-0.2. With this model, the 4-120 keV flux is (2.2 -0.4/+0.2)e-08 erg/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: Nicolas Dagoneau (CEA) (nicolas.dagoneau at cea.fr)