GCN Circular 42173
Subject
GRB 251002A - SVOM/ECLAIRs refined analysis
Event
Date
2025-10-09T06:55:38Z (a day ago)
From
SVOM_group <svomgroup@bao.ac.cn>
Via
Web form
M. G. Bernardini (INAF-OAB, LUPM), U. Jacob, F. Piron (LUPM), M. Brunet, O. Godet (IRAP), N. Dagoneau, B. Hubert, S. Schanne, A. Saccardi, D. Gotz (CEA/Irfu)
Using the event-by-event data downloaded through the X-band ground stations, we report further analysis of ECLAIRs observations of GRB 251002A (SVOM burst-id sb25100211).
The burst that triggered ECLAIRs onboard (Saccardi et al., GCN Circ. 42060) consists of a multiple peak structure with a duration of T90 = (8.2 -0.3/+1.82) s in the 4-120 keV energy band. After this main emission episode, the source is still visible through image deconvolution as a dim source up to about 30 s after T0 (T0 = 2025-10-02T20:14:54 s).
The time-averaged spectrum from T0-3 s to T0+8 s in the energy range 5-120 keV is best fitted by a cutoff power law model with index (0.72 +0.18/-0.20) and E0 = (79 +68/-26) keV. With this model, the total 4-120 keV fluence is (2.57 +/-0.03)e-6 erg/cm^2.
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. G. Bernardini (INAF-OAB, LUPM) (maria.bernardini at inaf.it)