Interactions of UHE cosmic ray nuclei with radiation during acceleration: consequences on the spectrum and composition

Abstract

In this paper, we study the diffusive shock acceleration of cosmic-ray protons and nuclei, taking into account all the relevant interaction processes with photon backgrounds. We investigate how the competition between protons and nuclei is modified by the acceleration parameters such as the acceleration rate, its rigidity dependence, the photon density and the confinement capability of the sources. We find that in the case of interaction-limited acceleration processes protons are likely to be accelerated to higher energies than nuclei, whereas for confinement-limited acceleration nuclei are accelerated to higher energies than protons. Finally, we discuss our results in the context of possible astrophysical accelerators, and in the light of recent cosmic-ray data.

14 pages, 11 figures A few paragraphs and one figure added for clarity, figures slightly redesigned, no changes in the results

References in corpus (4)

• Implications of the cosmic ray spectrum for the mass composition at the highest energies
• Cosmogenic Neutrinos from the propagation of Ultra High Energy Nuclei
• Signatures of the extragalactic cosmic-ray source composition from spectrum and shower depth measurements
• Fossil AGN jets as ultra high energy particle accelerators

Cited by in corpus (16)

• The Astrophysics of Ultrahigh Energy Cosmic Rays
• Cosmogenic Neutrinos: parameter space and detectabilty from PeV to ZeV
• Origin of the ankle in the ultra-high energy cosmic ray spectrum and of the extragalactic protons below it
• Extragalactic propagation of ultrahigh energy cosmic-rays
• Anisotropy vs chemical composition at ultra-high energies
• High-energy gamma-ray and neutrino backgrounds from clusters of galaxies and radio constraints
• Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
• Neutrino-heated winds from rotating proto-magnetars
• Constraining models for the origin of ultra-high-energy cosmic rays with a novel combined analysis of arrival directions, spectrum, and composition data measured at the Pierre Auger Observatory
• Acceleration and radiation of ultra-high energy protons in galaxy clusters
• Testing hadronic and photo-hadronic interactions as responsible for UHECR and neutrino fluxes from Starburst Galaxies
• A limit on the ultra-high-energy neutrino flux from lunar observations with the Parkes radio telescope
• Influence of cosmological models on the GZK horizon of ultrahigh energy protons
• Ultrahigh Energy Cosmic Rays and Neutrinos
• The flux suppression at the highest energies
• Extended clustering analyses to constrain the deflection angular scale and source density of the ultra-high-energy cosmic rays