TITLE: GCN CIRCULAR NUMBER: 42292 SUBJECT: GRB 251013C: SVOM/ECLAIRs refined analysis DATE: 25/10/15 15:52:54 GMT FROM: SVOM_group H. Yang, M. Brunet, O. Godet (IRAP), B. Hubert (CEA), F. Piron (LUPM), N. A. Rakotondrainibe, C. Adami (LAM) Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 251013C (SVOM burst-id sb2525101311, GCN 42222) detected at T0 = 2025-10-13T17:39:42, which was also detected by SVOM/GRM and Fermi/GBM (GCN 42221). The burst that triggered ECLAIRs consists of a single peak, with a typical fast-rising and exponential-decay profile, starting at T0-0.4 s and lasting about 30 s in the 4-120 keV energy band. The time-averaged spectrum from the peak (T0-0.4 s to T0+30 s) in the 4-120 keV energy range is well fitted by a power-law model with a photon index of 1.59 +/-0.03. With this model, the total 4-120 keV fluence is (1.95 + 0.02/-0.03)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: Hui Yang (IRAP) (hui.yang@irap.omp.eu).