# Particle Spectra and Mass Composition in the Ultra-High Energy Region in the Framework of the Galactic Origin of Cosmic Rays

## TL;DR

This paper explores a Galactic origin model for ultra-high energy cosmic rays, accounting for source acceleration limits, inhomogeneous galactic matter, and magnetic fields, to explain observed spectra and composition variations.

## Contribution

It presents a self-consistent Galactic origin scenario incorporating fractal-like matter distribution and Levy flights, aligning with recent experimental data on cosmic ray composition.

## Key findings

- Model explains cosmic ray spectra up to 10^{20} eV.
- Predictions align with recent composition measurements.
- Scenario suggests Galactic sources can account for ultra-high energies.

## Abstract

The possibility for a self-consistent description of all the basic features of the observed cosmic ray spectra and primary composition variations in the energy range of $10^{15}\div 10^{20}$ eV within the Galactic origin scenario is examined. We assume the existence of Galactic sources that accelerate particles up to $\sim 3\cdot 10^{18}Z$ eV and take into account a highly inhomogeneous (fractal-like) distribution of matter and magnetic fields in the Galaxy that leads to extremely large free paths of particles ("L\'{e}vy flights"), along with an overwhelming contribution to the cosmic ray fluxes observed above $\sim 10^{18}$ eV from particles reaching the Solar System without scattering. Our scenario was refined on the basis of recent experimental results on primary mass composition. Model predictions, which could be verified with the improved high-precision measurements in the nearest future are discussed.