The newborn black hole in GRB 191014C proves that it is alive

¹ ICRANet, Piazza della Repubblica 10, 65122 Pescara, Italy
e-mail: rahim.moradi@icranet.org, jorge.rueda@icra.it, ruffini@icra.it
² ICRA, Dipartimento di Fisica, Sapienza Università di Roma, P.le Aldo Moro 5, 00185 Rome, Italy
³ INAF, Osservatorio Astronomico d’Abruzzo, Via M. Maggini snc, 64100 Teramo, Italy
⁴ ICRANet-Ferrara, Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, 44122 Ferrara, Italy
⁵ Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, 44122 Ferrara, Italy
⁶ INAF, Istituto de Astrofisica e Planetologia Spaziali, Via Fosso del Cavaliere 100, 00133 Rome, Italy
⁷ INAF, Viale del Parco Mellini 84, 00136 Rome, Italy

Received: 18 November 2019
Accepted: 2 April 2021

Abstract

A multi-decade theoretical effort has been devoted to finding an efficient mechanism to use the rotational and electrodynamical extractable energy of a Kerr-Newman black hole (BH), to power the most energetic astrophysical sources such as gamma-ray bursts (GRBs) and active galactic nuclei. We show an efficient general relativistic electrodynamical process which occurs in the “inner engine” of a binary driven hypernova. The inner engine is composed of a rotating Kerr BH of mass M and dimensionless spin parameter α, a magnetic field of strength B₀ aligned and parallel to the rotation axis, and a very low-density ionized plasma. Here, we show that the gravitomagnetic interaction between the BH and the magnetic field induces an electric field that accelerates electrons and protons from the environment to ultrarelativistic energies emitting synchrotron radiation. We show that in GRB 190114C the BH of mass M = 4.4 M_⊙, α = 0.4, and B₀ ≈ 4 × 10¹⁰ G can lead to a high-energy (≳GeV) luminosity of 10⁵¹ erg s⁻¹. The inner engine parameters are determined by requiring (1) that the BH extractable energy explains the GeV and ultrahigh-energy emission energetics, (2) that the emitted photons are not subjected to magnetic-pair production, and (3) that the synchrotron radiation timescale agrees with the observed high-energy timescale. We find for GRB 190114C a clear jetted emission of GeV energies with a semi-aperture angle of approximately 60° with respect to the BH rotation axis.