A Magnetized Strongly Turbulent Corona as the Source of Neutrinos from NGC 1068
Year: 2024
Type: article
Abstract: The cores of active galactic nuclei are potential accelerators of 10–100 TeV cosmic rays, in turn producing high-energy neutrinos. This picture was confirmed by the compelling evidence of a TeV neutrino signal from the nearby active galaxy NGC 1068, leaving open the question of what is the site and mechanism of cosmic-ray acceleration. One candidate is the magnetized turbulence surrounding the central supermassive black hole. Recent particle-in-cell simulations of magnetized turbulence indicate that stochastic cosmic-ray acceleration is nonresonant, in contrast to the assumptions of previous studies. We show that this has important consequences on a self-consistent theory of neutrino production in the corona, leading to a more rapid cosmic-ray acceleration than previously considered. The turbulent magnetic-field fluctuations needed to explain the neutrino signal are consistent with a magnetically powered corona. We find that strong turbulence, with turbulent magnetic energy density higher than 1% of the rest-mass energy density, naturally explains the normalization of the IceCube neutrino flux, in addition to the neutrino spectral shape. Only a fraction of the protons in the corona, which can be directly inferred from the neutrino signal, are accelerated to high energies. Thus, in this framework, the neutrino signal from NGC 1068 provides a testbed for particle acceleration in magnetized turbulence.
Source: The Astrophysical Journal
Institution: Université Paris Diderot
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, Simons Foundation, Villum Fonden, European Commission, Agence Nationale de la Recherche, Nuclear Safety and Security Commission, Hellenic Foundation for Research and Innovation, Division of Physics, HORIZON EUROPE Marie Sklodowska-Curie Actions
Awards: Cosmic rays in the immediate local interstellar medium, G2637826787, WoU-MMA: Pinning the Generation of Ultra-High-Energy Cosmic Rays with First Principles Plasma Simulations, Collaborative Research: WoU-MMA: Multimessenger Plasma Physics Center (MPPC), G4149884836, G434337789, NBIA INTERACTIONS POSTDOCTORAL PROGRAMME, THE INTERPLAY OF RECONNECTION AND TURBULENCE IN RELATIVISTIC PLASMAS: THE CASE OF BLACK HOLE ACCRETION FLOWS AND CORONAE, G7875289405, G8543737702, G8761685661, G956605147, G978507763
OpenAlex ID: W4403198217