TITLE: GCN CIRCULAR NUMBER: 45181 SUBJECT: GRB 260718A: Fermi GBM Observation DATE: 26/07/18 17:24:01 GMT FROM: A. Holzmann Airasca at University of Trento and INFN Bari <a.holzmannairasca@unitn.it> A. Holzmann Airasca (UniTrento and INFN Bari) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 11:16:35.01 UT on 18 July 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260718A (trigger 806066200/260718470), which was also detected by SVOM/ECLAIRs (S. Antier et al. 2026, GCN 45177). The Fermi GBM on-ground location is consistent with the SVOM/ECLAIRs position. The angle from the Fermi LAT boresight is 31 degrees. The GBM light curve consists of a single emission episode with a duration (T90) of about 19 s (50-300 keV). The time-averaged spectrum from T0-3.8 to T0+16.3 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.29 +/- 0.05 and the cutoff energy, parameterized as Epeak, is 68 +/- 3 keV. The event fluence (10-1000 keV) in this time interval is (6.8 +/- 0.6)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-2.4 s in the 10-1000 keV band is 2.1 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/45181. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...