TITLE:   GCN CIRCULAR
NUMBER:  46038
SUBJECT: GRB 261019A: GECAM-B observation
DATE:    26/10/26 09:04:18 GMT
FROM:    guohx@ihep.ac.cn

Hao-Xuan Guo, Zheng-Hang Yu, Chen-Wei Wang, Chao Zheng, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:

GECAM-B was triggered in-flight by GRB 261019A, at 2026-10-19T09:14:09.100 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #45989), Insight-HXMT/HE (Guo et al., GCN #46013) and SVOM/GRM (Guo et al., GCN #46037).

According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of a pulse with a duration (T90) of 130 +2/-3 s.

The GECAM-B light curve can be found here:
https://www.bursthub.cn/gcn/2026/gecambgrb261019A.png

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).