TITLE: GCN CIRCULAR NUMBER: 30333 SUBJECT: GRB 210627B: BALROG localization (Fermi Trigger 646509445/ GRB 210627748) DATE: 21/06/27 19:37:43 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 646509445 at 17:57:20 on 27 June 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) = 230.5+/-2.5 deg Decl.(2000.0) = -5.9+/-1.5 deg We estimate an additional systematic error of 2 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB210627748/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB210627748/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB210627748/json