GCN Circular 44267
Subject
GRB 260409A: Insight-HXMT/HE detection
Event
Date
2026-04-11T15:14:51Z (22 days ago)
From
zhangjinpeng@ihep.ac.cn
Via
Web form
Jin-Peng Zhang, Chen-Wei Wang, Chao Zheng, and Shao-Lin Xiong (IHEP) report on behalf of the Insight-HXMT team:
At 2026-04-09T17:32:46.000 (T0), Insight-HXMT/HE detected GRB 260409A, which is also detected by Fermi/GBM (Fermi GBM Team, GCN #44249).
The Insight-HXMT/HE light curve mainly consists of several pulses with a T90 of 43 +6/-3 s. The 1 s peak rate, measured from T0+8.5 s, is 919 cnts/sec. Insight-HXMT/HE detected a total of 11547 counts from this burst.
The Insight-HXMT/HE light curve can be found here:
https://www.bursthub.cn//admin/static/hxmtgrb260409A.png
All measurements above are made with the CsI detectors of Insight-HXMT/HE operating in the low gain mode with the energy range of about 300-3000 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