\nu-production in Centaurus A and M87 from \gamma-ray interactions with the gas and dust at the sources

TL;DR

This paper models neutrino production from gamma-ray interactions with gas and dust in Centaurus A and M87, finding fluxes far below current detection limits and less competitive than cosmic ray acceleration scenarios.

Contribution

It introduces a simple model to estimate neutrino fluxes from gamma-ray interactions in active galactic nuclei, highlighting their insignificance compared to other astrophysical sources.

Findings

Neutrino fluxes are more than 6 orders below current upper limits.

Fluxes are not competitive with cosmic ray acceleration scenarios.

Estimated neutrino fluxes are below $10^{-13} s^{-1} GeV cm^{-2}$.

Abstract

Centaurus A and M87 are the closest galaxies with active galactic nuclei and TeV gamma-ray emission. The existence of such TeV radiation suggests the production of a neutrino flux from the photo- hadronic interactions of the gamma-photons of the active galaxies and their own gas and dust content. Using a simple model of Centaurus A and M87, the corresponding neutrino luminosities at source and their fluxes at Earth were calculated. The neutrino fluxes associated with the aforementioned process resulted to be $E^2 \Phi_{\nu + \bar{\nu}} < 10^{-13} s^{-1} GeV cm^{-2}$, more than 6 orders of magnitude below the modern upper limits from neutrino telescopes. It will be shown that, at high-energies relevant for neutrino astronomy, these neutrino fluxes are not competitive with those fluxes which could be produced from astrophysical scenarios involving cosmic ray acceleration.