TITLE: GCN CIRCULAR NUMBER: 42945 SUBJECT: GRB 251201A: GECAM-B observation of a burst DATE: 25/12/02 12:08:00 GMT FROM: Yue Wang Yue Wang, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team: GECAM-B was triggered on-ground by GRB 251201A, at 2025-12-01T04:37:04.100 UTC (denoted as T0), which is also detected by MAXI/GSC (MAXI team, GCN #42913) and SVOM/GRM (Yue Wang et al., GCN #42932). According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses followed by a possible flare with a total T90 of 47.7 +/-15.6 s. The GECAM-B light curve can be found here: https://www.bursthub.cn//admin/static/gecambgrb251201A.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).