GCN Circular 40978
Subject
GRB 250704B: Insight-HXMT detection
Event
Date
2025-07-05T15:09:12Z (a day ago)
From
Chenwei Wang at IHEP <cwwang@ihep.ac.cn>
Via
Web form
Chen-Wei Wang, Shao-Lin Xiong, Cheng-Kui Li, and Chao Zheng report on behalf of the Insight-HXMT team:
At 2025-07-04T08:16:27.100 (T0), Insight-HXMT/HE detected the short burst GRB 250704B/ EP250704a, which is also detected by SVOM/GRM (Wang et al., GCN #40940), Konus-Wind (Dmitry Frederiks et al., GCN # 40972) and EP (Li et al., GCN # 40941).
The Insight-HXMT/HE light curve mainly consists of double pulses with a T90 of 0.68 +0.34/-0.48 s.
The total counts from this burst is 2046 counts.
The HXMT/HE light curve can be found here:
https://www.bursthub.cn//admin/static/hxmtgrb250704B.png
All measurements above are made with the CsI detectors 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://www.hxmt.org.