GCN Circular 45136
Subject
GRB 260709A: GECAM-B observation
Event
Date
2026-07-11T05:57:32Z (a day ago)
From
zhangjinpeng@ihep.ac.cn
Via
Web form
Jin-Peng Zhang, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:
GECAM-B was triggered in-flight by GRB 260709A, at 2026-07-09T01:07:32.000 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #45121).
According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of several pulses, with a duration (T90) of 56 +5/-4 s.
The GECAM-B light curve can be found here:
https://www.bursthub.cn/gcn/2026/gecambgrb260709A.png
The time-averaged spectrum from T0 - 5 to T0 + 50 s (photon energy > 70 keV) is fitted by a power law function. The power law index is -2.38 +0.25/-0.25. The event fluence (10-1000 keV) in this time interval is (1.5 +0.5/-0.3)E-05 erg/cm^2.
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).