TITLE: GCN CIRCULAR NUMBER: 43787 SUBJECT: GRB 260219A: GECAM-B observation of a long burst DATE: 26/02/20 11:47:59 GMT FROM: zhangjinpeng@ihep.ac.cn Jin-Peng Zhang, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team: GECAM-B was triggered in-flight by GRB 260219A, at 2026-02-19T14:04:54.600 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #43785). According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of one pulse, with a duration (T90) of 13 +/- 4 s. The GECAM-B light curve can be found here: https://www.bursthub.cn//admin/static/gecambgrb260219A.png The time-averaged spectrum from T0 - 1.0 to T0 + 13.0 s (photon energy > 70 keV) is fitted by a power law function. The power law index is -2.16 +0.14/-0.16. The event fluence (10-1000 keV) in this time interval is (7.7 +0.9/-1.1)E-06 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). View this GCN Circular online at https://gcn.nasa.gov/circulars/43787. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...