GZK Photons as Ultra High Energy Cosmic Rays

Abstract

We calculate the flux of "GZK-photons", namely the flux of Ultra High Energy Cosmic Rays (UHECR) consisting of photons produced by extragalactic nucleons through the resonant photoproduction of pions, the so called GZK effect. We We calculate the flux of "GZK-photons", namely the flux of Ultra High Energy Cosmic Rays (UHECR) consisting of photons produced by extragalactic nucleons through the resonant photoproduction of pions, the so called GZK effect. We show that, for primary nucleons, the GZK photon fraction of the total UHECR flux is between $10^{-4}$ and $10^{-2}$ above $10^{19}$ eV and up to the order of 0.1 above $10^{20}$ eV. The GZK photon flux depends on the assumed UHECR spectrum, slope of the nucleon flux at the source, distribution of sources and intervening backgrounds. Detection of this photon flux would open the way for UHECR gamma-ray astronomy. Detection of a larger photon flux would imply the emission of photons at the source or new physics. We compare the photon fractions expected for GZK photons and the minimal predicted by Top-Down models. We find that the photon fraction above $10^{19}$ eV is a crucial test for Top-Down models.

21 pages, 18 figures with 35 panels in version 3 (substantial changes to the "Topological defects", "SHDM" and "Photon fractions" subsections were made with respect to version 2)

References in corpus (8)

• A new determination of the extragalactic diffuse gamma-ray background from EGRET data
• An upper limit to the photon fraction in cosmic rays above 10^19 eV from the Pierre Auger Observatory
• Study of Small-Scale Anisotropy of Ultrahigh Energy Cosmic Rays Observed in Stereo by HiRes
• Upper limit on the ultra-high-energy photon flux from AGASA and Yakutsk data
• On the status of superheavy dark matter
• UHECR Particle Spectra from Crypton Decays
• Fitting the HiRes Spectra and Monocular Composition
• Bounds on Relic Neutrino Masses in the Z-burst Model

Cited by in corpus (56)

• Tests of Lorentz invariance: a 2013 update
• Measurements of the Cosmic Ray Composition with Air Shower Experiments
• Cosmic Rays from the Knee to the Highest Energies
• Upper limit on the cosmic-ray photon flux above 10^19 eV using the surface detector of the Pierre Auger Observatory
• Upper limit on the cosmic-ray photon fraction at EeV energies from the Pierre Auger Observatory
• The Jem-Euso Mission
• An upper limit to the photon fraction in cosmic rays above 10^19 eV from the Pierre Auger Observatory
• Ultra-High-Energy Cosmic Rays: The Intersection of the Cosmic and Energy Frontiers
• Constraining heavy decaying dark matter with the high energy gamma-ray limits
• Constraints on the diffuse photon flux with energies above $10^{18}$ eV using the surface detector of the Telescope Array experiment
• Gamma-Ray Constraints on Maximum Cosmogenic Neutrino Fluxes and UHECR Source Evolution Models
• GZK photon constraints on Planck scale Lorentz violation in QED
• Mass composition of ultra-high-energy cosmic rays with the Telescope Array Surface Detector Data
• Cosmogenic photons as a test of ultra-high energy cosmic ray composition
• Ultra-High Energy Cosmic Rays and the GeV-TeV Diffuse Gamma-Ray Flux
• Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
• Constraints on the flux of primary cosmic-ray photons at energies E > 10^18 eV from Yakutsk muon data
• A search for photons with energies above $2\times 10^{17}$ eV using hybrid data from the low-energy extensions of the Pierre Auger Observatory
• Constraints on the flux of $\sim (10^{16}-10^{17.5})$ eV cosmic photons from the EAS-MSU muon data
• Prospective constraints on Lorentz violation from ultrahigh-energy photon detection
• GZK Photons in the Minimal Ultra High Energy Cosmic Rays Model
• Photon splitting constraint on Lorentz Invariance Violation from Crab Nebula spectrum
• Searches for Ultra-High-Energy Photons at the Pierre Auger Observatory
• Width of photon decay in magnetic field: elementary semiclassical derivation and sensitivity to Lorentz violation
• Non-Universal Spectra of Ultra-High Energy Cosmic Ray Primaries and Secondaries in a Structured Universe
• Characteristics of geomagnetic cascading of ultra-high energy photons at the southern and northern sites of the Pierre Auger Observatory
• The Spectral Shape and Photon Fraction as Signatures of the GZK-Cutoff
• High energy cosmic rays
• Snowmass-2013 Cosmic Frontier 3 (CF3) Working Group Summary: Non-WIMP dark matter
• Estimate of the fraction of primary photons in the cosmic-ray flux at energies ~10^17 eV from the EAS-MSU experiment data
• Cosmic rays at ultra high energies (Neutrinos!)
• On the acceleration of Ultra-High-Energy Cosmic Rays
• Estimating $\gamma \gamma$ absorption for UHE photons with lepton and hadron production
• Review of the Multimessenger Working Group at UHECR-2012
• Constraints on top-down models for the origin of UHECRs from the Pierre Auger Observatory data
• Identifying Nearby UHECR Accelerators using UHE (and VHE) Photons
• Quantum gravity phenomenology at the dawn of the multi-messenger era -- A review
• Improving photon-hadron discrimination based on cosmic ray surface detector data
• Mass composition of cosmic rays determined by muon fraction with ${\epsilon }_{thr.}\ge$ 1 GeV in air showers with energy greater than 5 EeV
• Search for point sources of ultra-high energy photons with the Telescope Array surface detector
• Neutrino Production in Electromagnetic Cascades: An extra component of cosmogenic neutrino at ultrahigh energies
• Lower limit on the ultra-high-energy proton-to-helium ratio from the measurements of the tail of $X_{\max }$ distribution
• Status of the Yakutsk air shower array and future plans
• Search for ultra-high energy photons through preshower effect with gamma-ray telescopes: Study of CTA-North efficiency
• The flux suppression at the highest energies
• Blazar jets as possible sources of ultra-high energy photons: a short review
• Ultra High Energy Cosmic Ray, Neutrino, and Photon Propagation and the Multi-Messenger Approach
• Heavy Quark Production in Ultra High Energy Cosmic Ray Interactions
• The End of the Rainbow: What Can We Say About the Extragalactic Sub-Megahertz Radio Sky?
• A relook at the GZK Neutrino-Photon Connection: Impact of Extra-galactic Radio Background & UHECR properties
• Report from the Multi-Messenger Working Group at UHECR-2014 Conference
• Ultra-high energy event KM3-230213A as a cosmogenic neutrino in light of minimal UHECR flux models
• Search for Ultra-High Energy Photons with the Pierre Auger Observatory
• Extreme high energy proton-gamma discrimination from space observations
• Constraints on secondary 10-100 EeV gamma ray flux in the minimal bottom-up model of Ultra High Energy Cosmic Rays
• An upper limit to photons from first data taken by the Pierre Auger Observatory