TITLE: GCN CIRCULAR NUMBER: 12370 SUBJECT: GRB 110918A: rest-frame energetics in gamma-gays DATE: 11/09/20 17:43:34 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks and V.Pal'shin on behalf of the Konus-WIND team, report: Basing on the Konus-Wind detection of GRB 110918A (Hurley et al., GCN 12357; Golenetskii et al. GCN 12362), assuming Gemini-N redshift z=0.982 (Levan et al., GCN 12368), and a standard cosmology model (H_0 = 71 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda = 0.73), we estimate the following rest-frame parameters of the prompt gamma-ray emission: the isotropic equivalent energy release is E_iso ~1.9x10^54 erg, the peak luminosity is L_iso_max ~ 4.4x10^54 erg/s, and the peak energy of the time-integrated spectrum is Ep_rest ~300 keV. This estimation of L_iso_max makes GRB 110918A the most luminous gamma-ray burst (with known redshift) ever observed by Konus-Wind.