TITLE:   GCN CIRCULAR
NUMBER:  46061
SUBJECT: GRB 261024D: GECAM-B observation
DATE:    26/10/27 14:59:59 GMT
FROM:    Xinghao Luo at IHEP <2952704891@qq.com>

Xing-Hao Luo, Chen-Wei Wang, Ren-Yang Zhao, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:

GECAM-B was triggered on-ground by GRB 261024D, at 2026-10-24T21:33:05.250 UTC (denoted as T0), which is also detected by AstroSat CZTI (A. Goyal.et., GCN#46040), NuSTAR (G. Waratkar et.al., GCN#46051) and Glowbug gamma-ray telescope (C. C. Cheung.et.al., GCN#46053).

According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses with a duration (T90) of 9.5 +1.0/-0.5 s.

The on-ground calculated location, using the GECAM-B trigger data, is RA = 208.64, Dec = 25.1, with a statistical uncertainty of 5.46 degrees.

The GECAM-B light curve can be found here:
https://www.bursthub.cn//gcn/2026/gecambgrb261024D.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).