High-energy neutrinos from the vicinity of the supermassive black hole in NGC 1068

TL;DR

This study investigates the origin of high-energy neutrinos from NGC 1068, suggesting the supermassive black hole's vicinity as the primary source based on multi-wavelength analysis and theoretical modeling.

Contribution

It provides a detailed multi-messenger analysis of NGC 1068 and identifies the black hole's accretion region as the likely neutrino production site, advancing understanding of neutrino origins.

Findings

Neutrino production is linked to the accretion disk region near the black hole.

Photon densities in the accretion region support proton interactions for neutrino generation.

The study constrains the astrophysical environment responsible for observed high-energy neutrinos.

Abstract

We present a comprehensive multi-messenger study of NGC 1068, the prototype Seyfert II galaxy recently associated with high-energy IceCube neutrinos. Various aspects of the source, including its nuclear activity, jet, outflow, and starburst region, are analyzed in detail using a multi-wavelength approach and relevant luminosities are derived. We then explore its gamma-ray and neutrino emissions and investigate potential mechanisms underlying these phenomena and their relations with the different astrophysical components to try to understand which one is responsible for the IceCube neutrinos. By first using simple order-of-magnitude arguments and then applying specific theoretical models, we infer that only the region close to the accretion disc around the supermassive black hole has both the right density of X-ray photons needed to provide the targets for protons to sustain neutrino production and of optical/infrared photons required to absorb the associated but unobserved gamma rays. We conclude by highlighting ongoing efforts to constrain a possible broad connection between neutrinos and active galactic nuclei, as well as future synergies between astronomical and neutrino facilities.