TITLE: GCN CIRCULAR NUMBER: 32389 SUBJECT: GRB 220711C: Fermi GBM Observation DATE: 22/07/13 21:56:21 GMT FROM: Stephen Lesage at Fermi-GBM Team S. Lesage (UAH) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 16:11:58.54 UT on 11 July 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220711C (trigger 679248723/220711675) which was also detected by Konus-Wind (A. Ridnaia, et al. 2022, GCN 32382), Swift/BAT-GUANO (G. Raman et al. 2022, GCN 32384), and localized by IPN (D. Svinkin et al. 2022, GCN 32373). The on-ground calculated location, using the GBM trigger data, is RA = 81.06, DEC = -48.16 (J2000 degrees, equivalent to 05h 24m, -48d 10'), with an uncertainty of 3.5 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ). The Fermi GBM on-ground location is consistent with the IPN triangulation. The angle from the Fermi LAT boresight is 130 degrees. The GBM light curve consists of a single emission episode with a duration (T90) of about 0.3 s (10-1000 keV). The time-averaged spectrum from T0-0.06 to T0+0.26 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.1 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 972.6 +/- 136.0 keV. The event fluence (10-1000 keV) in this time interval is (1.51 +/- 0.08)E-06 erg/cm^2. The 64-ms peak photon flux measured starting from T0+0 s in the 10-1000 keV band is 13.6 +/- 1.4 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/"