TITLE: GCN CIRCULAR NUMBER: 35533 SUBJECT: GRB 240112C: Fermi GBM Detection DATE: 24/01/13 16:09:48 GMT FROM: Peter Veres at University of Alabama in Huntsville P. Veres (UAH), R. Hamburg (CNRS/IN2P3), A. Myers (NPP/GSFC) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 17:37:25.12 UT on 12 January 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240112C (trigger 726773850/240112734). GRB 240112C was also localized by Swift BAT and XRT (Eyles-Ferris et al., GCN #35522). The Fermi GBM on-ground Localization is consistent with the Swift position. The angle from the Fermi LAT boresight is 43 degrees. The GBM light curve consists of two pulses with a duration (T90) of about 5.3 s (50-300 keV). The time-averaged spectrum from T0-0.6 to T0+6.3 s is best fit by a Band function with with Epeak= 71 +/- 6 keV, alpha = -1.26 +/- 0.08 and beta = -2.34 +/- 0.10. The event fluence (10-1000 keV) in this time interval is (4.8 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.064 s in the 10-1000 keV band is 20.2 +/- 0.4 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/"