# Linking High-Energy Cosmic Particles by Black-Hole Jets Embedded in Large-Scale Structures

## TL;DR

This paper proposes that black hole jets in galaxy clusters can simultaneously explain the origins of ultrahigh-energy cosmic rays, PeV neutrinos, and gamma rays, unifying these phenomena within a single astrophysical framework.

## Contribution

It introduces a model where black hole jets in galaxy clusters produce and accelerate cosmic rays, neutrinos, and gamma rays, linking these high-energy phenomena.

## Key findings

- Model reproduces the observed UHECR spectrum and composition.
- Explains IceCube neutrino flux and Fermi gamma-ray background.
- Consistent with energy output estimates from black hole jets.

## Abstract

The origin of ultrahigh-energy cosmic rays (UHECRs) is a half-century old enigma (Linsley 1963). The mystery has been deepened by an intriguing coincidence: over ten orders of magnitude in energy, the energy generation rates of UHECRs, PeV neutrinos, and isotropic sub-TeV gamma rays are comparable, which hints at a grand-unified picture (Murase and Waxman 2016). Here we report that powerful black hole jets in aggregates of galaxies can supply the common origin of all of these phenomena. Once accelerated by a jet, low-energy cosmic rays confined in the radio lobe are adiabatically cooled; higher-energy cosmic rays leaving the source interact with the magnetized cluster environment and produce neutrinos and gamma rays; the highest-energy particles escape from the host cluster and contribute to the observed cosmic rays above 100 PeV. The model is consistent with the spectrum, composition, and isotropy of the observed UHECRs, and also explains the IceCube neutrinos and the non-blazar component of the Fermi gamma-ray background, assuming a reasonable energy output from black hole jets in clusters.