Revealing the Production Mechanism of High-Energy Neutrinos from NGC 1068

Abstract

The detection of high-energy neutrino signals from the nearby Seyfert galaxy NGC 1068 provides us with an opportunity to study nonthermal processes near the center of supermassive black holes. Using the IceCube and latest Fermi-LAT data, we present general multimessenger constraints on the energetics of cosmic rays and the size of neutrino emission regions. In the photohadronic scenario, the required cosmic-ray luminosity should be larger than about 1-10 percent of the Eddington luminosity, and the emission radius should be less than about 15 Schwarzschild radii in low-beta plasma and less than about 3 Schwarzschild radii in high-beta plasma. The leptonic scenario overshoots the NuSTAR or Fermi-LAT data for any emission radii we consider, and the required gamma-ray luminosity is much larger than the Eddington luminosity. The beta decay scenario also violates not only the energetics requirement but also gamma-ray constraints especially when the Bethe-Heitler and photomeson production processes are consistently considered. Our results rule out the leptonic and beta decay scenarios in a nearly model-independent manner, and support hadronic mechanisms in magnetically-powered coronae if NGC 1068 is a source of high-energy neutrinos.

15 pages, 7 figures, accepted for publication in ApJ, minor changes

References in corpus (11)

• On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
• Constraining High-Energy Cosmic Neutrino Sources: Implications and Prospects
• Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube
• ALMA images the many faces of the NGC1068 torus and its surroundings
• Thermal imaging of dust hiding the black hole in the Active Galaxy NGC 1068
• Inferring the flavor of high-energy astrophysical neutrinos at their sources
• Angular Momentum Transport and Particle Acceleration during Magnetorotational Instability in a Kinetic Accretion Disk
• Disentangling the Hadronic Components in NGC 1068
• Jet Power of Jetted Active Galactic Nuclei: Implication for Evolution and Unification
• The neutrino background from non-jetted active galactic nuclei
• ALMA detection of parsec-scale blobs at the head of kiloparsec-scale jet in the nearby Seyfert galaxy NGC 1068

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• Revisiting Disk Winds in Active Galactic Nuclei as an Origin of Cosmic Gamma-ray and Neutrino Backgrounds
• Interpreting Swift and NuSTAR Observations of the Low-Luminosity Active Galactic Nucleus NGC 4278 with Radiatively Inefficient Accretion Flows and Implications for Neutrino Emission