The impact of photonuclear reaction models on propagation of ultrahigh energy cosmic rays

Abstract

Ultrahigh energy cosmic ray (UHECR) nuclei with Lorentz factors greater than about $10^9$ lose their energies by the photodisintegration with cosmic microwave background photons in intergalactic space. The photodisintegration is a main process of the energy losses at the highest energies, so it is important to understand the model dependence of the photodisintegration to simulate propagation of UHECR nuclei. We implemented photonuclear reaction models which were obtained using calculations of the random-phase approximation (RPA) in a cosmic ray propagation code CRPropa and simulated the cosmic ray propagation. We present the comparison of the simulated observables such as energy spectra and compositions between the models.