TITLE: GCN CIRCULAR NUMBER: 31239 SUBJECT: GRB 211216A: BALROG localization (Fermi Trigger 661329957 / GRB 211216282) DATE: 21/12/16 07:22:31 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 661329957 at 06:45:52 on 16 Dec. 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) = 51.0+/-2.4 deg Decl.(2000.0) = -62.2+/-4.0 deg We estimate an additional systematic error of 2 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB211216282/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB211216282/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB211216282/json