TITLE: GCN CIRCULAR NUMBER: 43983 SUBJECT: GRB 260308A: Insight-HXMT/HE detection DATE: 26/03/13 11:02:02 GMT FROM: Xinghao Luo at IHEP <2952704891@qq.com> Xing-Hao Luo, Chen-Wei Wang, Chao Zheng, Hao-Xuan Guo, Xiao-Bo Li and Shao-Lin Xiong (IHEP) report on behalf of the Insight-HXMT team: At 2026-03-08T20:05:53.000 (T0), Insight-HXMT/HE detected the burst GRB 260308A, which is also detected by Fermi/GBM (Fermi GBM Team, GCN #43949) and SVOM/GRM (Xing-Hao Luo et.al., GCN#43960). The Insight-HXMT/HE light curve mainly consists of a single pulse with a T90 of 0.3 +0.2/-0.1 s. The 1s peak rate, measured from T0-0.65 s, is 625 cnts/sec. Insight-HXMT/HE detected a total of 512 counts form this burst. The HXMT/HE light curve can be found here: https://www.bursthub.cn//admin/static/hxmtgrb260308A.png All measurements above are made with the CsI detectors of Insight-HXMT/HE operating in the regular mode with the energy range of about 60-900 keV (deposited energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the telescope. Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information about it could be found at: http://hxmten.ihep.ac.cn/ View this GCN Circular online at https://gcn.nasa.gov/circulars/43983. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...