Spectra and Mass Composition of Ultrahigh-Energy Cosmic Rays from Point Sources

TL;DR

This paper models the spectra and mass composition of ultrahigh-energy cosmic rays from nearby Seyfert galaxy sources, successfully fitting observational data from HiRes and Pierre Auger Observatory with various spectral indices.

Contribution

It introduces a model linking Seyfert galaxy sources to cosmic ray spectra and composition, fitting data with different spectral parameters.

Findings

Model can describe experimental data from multiple observatories.

Mass composition at sources is assumed to be mixed.

Different spectral indices g0 fit the data well.

Abstract

We present spectra and mass composition of cosmic rays incoming to the Earth in the energy range (0.5-2)10^20 eV. As their sources we consider Seyfert galaxies located at distances < 40 Mpc, following an acceleration model for such moderate-power objects. Mass composition of the particles at sources is assumed to be mixed. Generation spectra are described by a function E^(-g0), where g0 is an arbitrary parameter. It is shown that the assumptions adopted make it possible to describe experimental data provided by HiRes and Pierre Auger Observatory, using different values of g0.