TITLE:   GCN CIRCULAR
NUMBER:  42669
SUBJECT: GRB 251025B: SVOM/ECLAIRs refined analysis
DATE:    25/11/13 14:50:40 GMT
FROM:    SVOM_group <svomgroup@bao.ac.cn>

M. Brunet (IRAP), F. Lacreu (IAP), F. Daigne (IAP), O. Godet (IRAP),  S. Hussein (IJCLab)

Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 251025B (SVOM burst-id sb25102502, GCN 42347) detected at T0 = 2025-10-25T14:24:05.

The burst that triggered ECLAIRs consists of a multiple peak lightcurve, lasting about 80 s in the 4-120 keV energy band.

The time-averaged spectrum from T0-21 s to T0+39 s in the 5-120 keV energy range is best fitted by a power-law model with a photon index of 1.60 +/-0.06. With this model, the total 4-120 keV fluence is (1.52 +0.06/-0.11)e-06 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: Marius Brunet (IRAP) (marius.brunet at irap.omp.eu)