TITLE: GCN CIRCULAR NUMBER: 37813 SUBJECT: GRB 241016B: Fermi GBM Observations DATE: 24/10/18 13:32:44 GMT FROM: Elisabetta Bissaldi at Politecnico and INFN Bari E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 11:12:40.13 UT on 16 October 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 241016B (trigger 750769965/241016467), which was also detected by SVOM/GRM (Zhang et al. 2024, GCN 37803) and by Swift/BAT-GUANO (DeLaunay et al. 2024, GCN 37806). The angle from the Fermi LAT boresight is 86 degrees. The GBM light curve consists of two peaks with a duration (T90) of about 0.8 s (50-300 keV). The time-averaged spectrum from T0-0.6s to T0+0.7s is best fit by a power law function with an exponential high-energy cutoff. The power law index is 0.0 +/- 0.5 and the cutoff energy, parameterized as Epeak, is 840 +/- 380 keV. The event fluence (10-1000 keV) in this time interval is (4.1 +/- 0.5)E-07 erg/cm^2. The 64-msec peak photon flux measured starting from T0-0.064 s in the 10-1000 keV band is 6.4 +/- 0.7 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/"