TITLE: GCN CIRCULAR NUMBER: 31056 SUBJECT: GRB 211023A: A BdHN of type I DATE: 21/11/08 19:17:11 GMT FROM: Remo Rufinni at ICRA <ruffini@icra.it> Y. Aimuratov, L. Becerra, C.L. Bianco, Y-C. Chen, C. Cherubini, S. Eslamzadeh, S. Filippi, M. Karlica, Liang Li, G.J. Mathews, R. Moradi, M. Muccino, G.B, Pisani, F. Rastegar Nia, J.A. Rueda, R. Ruffini, N. Sahakyan, Y. Wang, S.S. Xue, on behalf of the ICRANet and ICRA-USTC team, report: The identification of the redshift z=0.36 of GRB 211023A (A. Pozanenko et al. 2021, GCN 31053), with the isotropic energy of Eiso~6x10^52 erg in 10-1000 keV (S. Lesage et al. 2021, GCN 30965, S. Poolakkil et al. 2021, GCN 30998), qualify GRB 211023A as a BdHN I, confirmed by the observation of the GeV emission (N. Di Lalla et al. 2021, GCN 30961), originated from the black hole (R. Ruffini et al. 2019 ApJ 886 82, Moradi et al 2021. Phys. Rev. D 104, 063043) and the afterglow emission (Jan Strobl et al. 2021 GCN 31042) originated from the newborn neutron star (J.A. Rueda et al. 2020 ApJ 893 148). Following Ruffini et al. 2021 (MNRAS, 504, 5301, doi:10.1093/mnras/stab724) we indicate the appearance of the peak of optical supernova to be observed at (18.4+/-2.6) days after the trigger (November 10th 2021, uncertainty from November 8th 2021 to November 12th 2021), with the bolometric optical luminosity of L=(9.0+/-2.7)x10^42 erg/s. The follow-up optical observations for the SN are recommended. -- Prof. Remo Ruffini APS Fellow Google Fellow Director of ICRANet Piazza della Repubblica 10 65122 Pescara (PE) Italy mobile: +39 339 4752566 Tel. Rome +39 06 49914304 Tel. Pescara +39 085 23054201 Fax: +39 085 4219252 e-mail: ruffini@icra.it