TITLE: GCN CIRCULAR NUMBER: 43561 SUBJECT: GRB 260128B: SVOM detection of a burst through offline search DATE: 26/01/29 19:08:31 GMT FROM: SVOM_group <svomgroup@bao.ac.cn> M. Brunet (IRAP), S. Le Stum, A. Coleiro (APC), O. Godet (IRAP),report on behalf of the SVOM team: The SVOM/ECLAIRs telescope detected a transient source, labelled GRB 260128B, starting at 2026-01-28T06:48:34.72 UTC (T0), through an offline search with the event-by-event data downloaded through the X-band ground station. The burst was detected within several energy ranges and timescales. The best detection is obtained by the Image Trigger with a signal-to-noise ratio of 7.5 within 4-20 keV over a time window of 10.24 seconds starting at T0-10.24s. The lightcurve shows a single peaked structure lasting around 4s. The localization of the source is RA, Dec = 27.734, -25.867 degrees: RA (J2000) = 01h50m56.16s Dec (J2000) = -25d52m01.20s with a 90% C.L. radius of 12.0 arcmin (including systematic error of 6 arcmin added in quadrature). We note that no bright catalogued X-ray sources are found in the error box. The Space 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 APC, CEA, CNES, and IRAP. The SVOM point of contact for this event is : Sébastien Le Stum : lestum at apc.in2p3.fr Please contact him by email if you require additional information regarding the SVOM follow-up of this burst. View this GCN Circular online at https://gcn.nasa.gov/circulars/43561. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...