//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 30588 SUBJECT: GRB 210803A: BALROG localization (Fermi Trigger 649684549 / GRB 210803497) DATE: 21/08/03 12:21:12 GMT FROM: Jochen Greiner at MPE,Garching B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report: The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger 649684549 at 11:55:44 on 03 Aug. 2021 were automatically fitted for spectrum and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427; Berlato et al. 2019, ApJ 873, 60). The best-fit position (1 sigma statistical errors) is: RA(2000.0) = 202.4+/-0.4 deg Decl.(2000.0) = -33.9+/-0.7 deg We estimate an additional systematic error of 2 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB210803497/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB210803497/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB210803497/json //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 30595 SUBJECT: GRB 210803A: Fermi GBM observation DATE: 21/08/04 09:07:17 GMT FROM: Elisabetta Bissaldi at INFN,Bari E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 11:55:44.40 UT on 3 August 2021, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 210803A (trigger 649684549 / 210803497). The on-ground calculated location, using the GBM trigger data, is RA = 218.7, DEC = -21.4 (J2000 degrees, equivalent to 14h 34m, -21d 24'), with a statistical uncertainty of 1 degree (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 angle from the Fermi LAT boresight at the GBM trigger time is 98 degrees. The GBM light curve consists of bright, FRED-like emission episode with a duration (T90) of about 9 s (50-300 keV). The time-averaged spectrum from T0 to T0+9 s is well fit by a Band function with Epeak = 164 +/- 19 keV, alpha = -1.20 +/- 0.05, and beta = -2.06 +/- 0.07. The event fluence (10-1000 keV) in this time interval is (1.28 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.4 s in the 10-1000 keV band is 35.7 +/- 0.6 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/"