Cosmogenic gamma-rays and neutrinos constrain UHECR source models

<p>When ultra-high-energy cosmic rays (UHECRs) propagate through the universe they produce secondary neutrinos as well as photons, electrons and positrons (initiating electromagnetic cascades) in different kinds of interactions. These neutrinos and electromagnetic cascades are detected at Eart...

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Main Authors: van Vliet, A, Alves Batista, R, Hörandel, JR
Format: Conference item
Language:English
Published: Sissa Medialab 2017
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author van Vliet, A
Alves Batista, R
Hörandel, JR
author_facet van Vliet, A
Alves Batista, R
Hörandel, JR
author_sort van Vliet, A
collection OXFORD
description <p>When ultra-high-energy cosmic rays (UHECRs) propagate through the universe they produce secondary neutrinos as well as photons, electrons and positrons (initiating electromagnetic cascades) in different kinds of interactions. These neutrinos and electromagnetic cascades are detected at Earth as isotropic extragalactic fluxes. The level of these fluxes can be predicted and used to constrain UHECR source models.</p> <p>The public astrophysical simulation framework CRPropa 3, designed for simulating the propagating extraterrestrial ultra-high energy particles, is ideally suited for this purpose. CRPropa includes all relevant UHECR interactions as well as secondary neutrino and electromagnetic cascade production and propagation. It is designed for high-performance computing and provides the flexibility to scan large parameter ranges of UHECR models.</p> <p>The expected cosmogenic neutrino and gamma-ray spectra depend strongly on the evolution with redshift of the UHECR sources and on the chemical composition of UHECRs at injection. The isotropic diffuse gamma-ray background measured by Fermi/LAT is already close to touching upon a model with co-moving source evolution and with the chemical composition, spectral index and maximum acceleration energy optimized to provide the best fit to the UHECR spectrum and composition measured by the Pierre Auger Collaboration. Additionally, the detectable fraction of protons present at the highest energies in UHECRs is shown as a function of the evolution of UHECR sources for a range of sensitivities of neutrino detectors at an energy of ∼1 EeV.</p> <p>Neutrino and gamma-ray measurements are starting to constrain realistic UHECR models. Current and future neutrino experiments with sensitivities in the range of ∼10−8 - 10−10 GeV cm−2 s−1 sr−1 for the single-flavor neutrino flux at ∼1 EeV will be able to significantly constrain the proton fraction for realistic source evolution models.</p>
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spelling oxford-uuid:39263490-c30b-40e8-8096-6a89a897941a2022-03-26T13:53:55ZCosmogenic gamma-rays and neutrinos constrain UHECR source modelsConference itemhttp://purl.org/coar/resource_type/c_5794uuid:39263490-c30b-40e8-8096-6a89a897941aEnglishSymplectic ElementsSissa Medialab2017van Vliet, AAlves Batista, RHörandel, JR<p>When ultra-high-energy cosmic rays (UHECRs) propagate through the universe they produce secondary neutrinos as well as photons, electrons and positrons (initiating electromagnetic cascades) in different kinds of interactions. These neutrinos and electromagnetic cascades are detected at Earth as isotropic extragalactic fluxes. The level of these fluxes can be predicted and used to constrain UHECR source models.</p> <p>The public astrophysical simulation framework CRPropa 3, designed for simulating the propagating extraterrestrial ultra-high energy particles, is ideally suited for this purpose. CRPropa includes all relevant UHECR interactions as well as secondary neutrino and electromagnetic cascade production and propagation. It is designed for high-performance computing and provides the flexibility to scan large parameter ranges of UHECR models.</p> <p>The expected cosmogenic neutrino and gamma-ray spectra depend strongly on the evolution with redshift of the UHECR sources and on the chemical composition of UHECRs at injection. The isotropic diffuse gamma-ray background measured by Fermi/LAT is already close to touching upon a model with co-moving source evolution and with the chemical composition, spectral index and maximum acceleration energy optimized to provide the best fit to the UHECR spectrum and composition measured by the Pierre Auger Collaboration. Additionally, the detectable fraction of protons present at the highest energies in UHECRs is shown as a function of the evolution of UHECR sources for a range of sensitivities of neutrino detectors at an energy of ∼1 EeV.</p> <p>Neutrino and gamma-ray measurements are starting to constrain realistic UHECR models. Current and future neutrino experiments with sensitivities in the range of ∼10−8 - 10−10 GeV cm−2 s−1 sr−1 for the single-flavor neutrino flux at ∼1 EeV will be able to significantly constrain the proton fraction for realistic source evolution models.</p>
spellingShingle van Vliet, A
Alves Batista, R
Hörandel, JR
Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title_full Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title_fullStr Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title_full_unstemmed Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title_short Cosmogenic gamma-rays and neutrinos constrain UHECR source models
title_sort cosmogenic gamma rays and neutrinos constrain uhecr source models
work_keys_str_mv AT vanvlieta cosmogenicgammaraysandneutrinosconstrainuhecrsourcemodels
AT alvesbatistar cosmogenicgammaraysandneutrinosconstrainuhecrsourcemodels
AT horandeljr cosmogenicgammaraysandneutrinosconstrainuhecrsourcemodels