TITLE: GCN CIRCULAR NUMBER: 36017 SUBJECT: GRB 240402B: GECAM-C detection DATE: 24/04/03 17:01:02 GMT FROM: Kai <wcxuemail@gmail.com> Wang-Chen Xue, Shao-Lin Xiong, Chao Zheng, Yanqiu Zhang, and Chengkui Li, report on behalf of the GECAM team: GECAM-C observed a long burst, GRB 240402A at 2024-04-02T08:47:46 UTC (denoted as T0), which has been detected by LEIA (GCN 36016) and Konus-Wind. According to the observation data of GECAM-C, this burst mainly consists of two peaks with a duration (T90) of 6.55 +/- 0.52 sec (15-350 keV). The GECAM-C localization is consistent with the LEIA localization (GCN 36016) within the error. The time-averaged spectrum of GECAM-C data from T0-7.0 to T0+7.0 s could be adequately fit by a cut-off power-law with photon index alpha of -0.62 (-0.14, +0.13), and peak energy Ep of 66 (-3, +3) keV. The corresponding burst fluence is 7.69 (-0.24, +0.25) * 10^-7 erg/cm^2 in 15-350 keV. We note that these results are preliminary and refined analysis will be reported later. 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/36017. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...