TITLE: GCN CIRCULAR NUMBER: 36106 SUBJECT: EP240413a: Upper limits from GECAM-B Observation DATE: 24/04/15 04:55:17 GMT FROM: Yue Wang <m18509381757@163.com> Yue Wang, Shao-Lin Xiong, Chen-wei Wang, Wen-long Zhang, Cheng-kui Li and Chao Zheng, report on behalf of the GECAM team: GECAM-B was observing normally and covered the sky region of EP240413a (Lian et al., GCN 36086) at event time 2024-04-13T14:39:37 (UTC). The smallest incident angle of GECAM-B GRD detectors is about 21.3 deg for the WXT location (RA=228.794 deg, Dec=-18.8 deg). There was no GECAM-B in-flight trigger around the event time of EP240413a. An automated, blind search for gamma-ray bursts of GECAM-B data found no burst candidates. The targeted search was run within -50 s ~ 250 s around event time, and also identified no counterpart candidates. With the three typical GRB spectral models, integration time of 10 s and the WXT localization, the 3-sigma upper-limits of fluence (15 - 300 keV, incident energy) are reported below: Band model 1 (alpha=-1.9, beta=-3.7, Ep=70 keV): 7.5e-6 erg cm^-2 Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV): 6.6e-6 erg cm^-2 Band model 3 (alpha=0.0, beta=-1.5, Ep=1000 keV): 3.5e-6 erg cm^-2 All measurements above are made with all GRD detectors. 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/36106. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...