TITLE: GCN CIRCULAR NUMBER: 44157 SUBJECT: GRB 260330B: SVOM detection of a burst DATE: 26/03/30 14:50:52 GMT FROM: SVOM_group <svomgroup@bao.ac.cn> G. X. Lan, S. Guillot, H. Yang, O. Godet (IRAP), report on behalf of the SVOM mission team: At 2026-03-30T14:19:57 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 260330B (SVOM burst-id sb26033003). The following trigger information was received on the ground with low latency by the SVOM VHF Alert Network. The burst was detected both by the Count-Rate Trigger (CRT) and the Image Trigger (IMT), which produced a sequence of 9 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 12.13 in the [5-20] keV energy band over a time window of 40.96 seconds starting at 2026-03-30T14:19:31. The localization of the best alert is R.A., Dec. 252.555, 36.862 degrees: R.A. (J2000) = 16h50m13s Dec. (J2000) = 36d51m44s with a 90% confidence level (C.L.) radius of 6.66 arcmin (including systematic error of 2 arcmin added in quadrature). The SVOM/ECLAIRs light curve showed multiple broad peak structures with a T90 duration of about 20.844 (-3.025 / +7.55) s. This burst was also detected by SVOM/GRM with a significance of 9.10. SVOM slewed to the burst. No X-ray observation could be performed by SVOM/MXT for the time being. No optical observation could be performed by SVOM/VT for the time being. 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. SVOM/ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. SVOM/GRM was developed by the Institute of High Energy Physics (IHEP) of CAS. SVOM/MXT was developed jointly by CNES, CEA-IRFU, CNRS-IJCLab, University of Leicester, MPE. The Burst Advocate (BA) on shift for this alert is Guangxuan Lan: glan@irap.omp.eu. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/44157. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...