GCN Circular 43299
Subject
GRB 251230A / EP251230a: Insight-HXMT/HE detection
Event
Date
2026-01-02T12:17:17Z (6 days ago)
From
guohx@ihep.ac.cn
Via
Web form
Hao-Xuan Guo, Chen-Wei Wang, Cheng-Kui Li, Shao-Lin Xiong, and Chao Zheng (IHEP) report on behalf of the Insight-HXMT team:
At 2025-12-30T01:22:22.000 (T0), Insight-HXMT/HE detected a burst, GRB 251230A / EP251230a, which is also detected by Swift (Lanava et al., GCN #43252) and EP-WXT (Li et al., GCN #43255 and Wang et al., GCN #43272).
The Insight-HXMT/HE light curve mainly consists of multiple pulses with T90 of 54.4 +11.6/-8.4 s. The 1s peak rate, measured from T0-0.70 s, is 797 cnts/sec. Insight-HXMT/HE detected a total of 10,311 counts from this burst.
The Insight-HXMT /HE light curve can be found here:
https://www.bursthub.cn//admin/static/hxmtgrb251230A.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://www.hxmt.org