Revisiting the propagation of highly-energetic gamma rays in the Galaxy

Abstract

Recent gamma-ray observations have detected photons up to energies of a few PeV. These highly energetic gamma rays are emitted by the most powerful sources in the Galaxy. Propagating over astrophysical distances, gamma rays might interact with background photons producing electron-positron pairs, then deflected by astrophysical magnetic fields. In turn, these charged particles might scatter through inverse Compton galactic radiation fields, triggering electromagnetic cascades. In this scenario, the characterisation of astrophysical environment in which gamma rays travel, specifically background photons and magnetic fields, is crucial. We explore the impact of propagation effects on observables at Earth by simulating galactic sources emitting gamma rays with energy between $100\text{GeV}$ and $100\text{PeV}$. We analyse the imprint of the galactic environment on observed energy spectra and arrival direction maps, revealing gamma-ray absorption features in the former and ``deflection" of gamma rays in the latter. Specifically, owing to interstellar radiation field spatial distribution and the galactic magnetic field structure, propagation effects on observables are found to be related to the specific gamma-ray source position and to the prompt emission model. Detailed investigations of the propagation effect on galactic gamma rays will improve the robustness of both current and future gamma-ray detections and indirect dark matter searches.

arXiv comment17 pages, 24 figures and 1 table. Published in PRD

References in corpus (84)

• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• Cosmic strings
• Planck 2018 results. V. CMB power spectra and likelihoods
• Evidence for strong extragalactic magnetic fields from Fermi observations of TeV blazars
• The extragalactic optical-infrared background radiations, their time evolution and the cosmic photon-photon opacity
• Extragalactic Background Light Inferred from AEGIS Galaxy SED-type Fractions
• A New Model of the Galactic Magnetic Field
• Modeling the Extragalactic Background Light from Stars and Dust
• Semi-analytic modeling of the EBL and consequences for extragalactic gamma-ray spectra
• Ultra-high energy cosmic rays without GZK cutoff
• CRPropa 3 - a Public Astrophysical Simulation Framework for Propagating Extraterrestrial Ultra-High Energy Particles
• COBE's Galactic Bar and Disk
• GALPROP WebRun: an internet-based service for calculating galactic cosmic ray propagation and associated photon emissions
• Ultrahigh energy neutrino scattering onto relic light neutrinos in galactic halo as a possible source of highest energy extragalactic cosmic rays
• The First LHAASO Catalog of Gamma-Ray Sources
• Extremely high energy cosmic rays from relic particle decays
• 3HWC: The Third HAWC Catalog of Very-High-Energy Gamma-ray Sources
• Sensitivity of gamma-ray telescopes for detection of magnetic fields in intergalactic medium
• A new estimate of the extragalactic radio background and implications for ultra-high-energy gamma-ray propagation
• Attenuation of VHE gamma rays by the Milky Way interstellar radiation field
• Search for Spatial Extension in High-Latitude Sources Detected by the Fermi Large Area Telescope
• A radiation transfer model for the Milky-Way: I. Radiation fields and application to High Energy Astrophysics
• The high energy cosmic ray spectrum from relic particle decay
• An observational determination of the evolving extragalactic background light from the multiwavelength HST/CANDELS survey in the Fermi and CTA era
• The nature of the Diffuse Gamma-Ray Background
• Measurement of ultra-high-energy diffuse gamma-ray emission of the Galactic plane from 10 TeV to 1 PeV with LHAASO-KM2A
• Searching for galactic cosmic ray pevatrons with multi-TeV gamma rays and neutrinos
• Absorption of Very High Energy Gamma Rays in the Milky Way
• High-Energy Gamma Rays from the Milky Way: Three-Dimensional Spatial Models for the Cosmic-Ray and Radiation Field Densities in the Interstellar Medium
• Nonthermal particles and photons in starburst regions and superbubbles
• Cosmogenic photon and neutrino fluxes in the Auger era
• CRPropa 3.2 -- an advanced framework for high-energy particle propagation in extragalactic and galactic spaces
• TeV Halos are Everywhere: Prospects for New Discoveries
• An Ultrahigh-energy $\gamma$-ray Bubble Powered by a Super PeVatron
• The Coherent Magnetic Field of the Milky Way
• An Empirical Determination of the Intergalactic Background Light from UV to FIR Wavelengths Using FIR Deep Galaxy Surveys and the Gamma-ray Opacity of the Universe
• The Gamma-Ray Window to Intergalactic Magnetism
• Gamma-Ray and Neutrino Backgrounds as Probes of the High-Energy Universe: Hints of Cascades, General Constraints, and Implications for TeV Searches
• A self-consistent model of Galactic stellar and dust infrared emission and the abundance of polycyclic aromatic hydrocarbons
• Constraining heavy decaying dark matter with the high energy gamma-ray limits
• Gamma-ray bounds from EAS detectors and heavy decaying dark matter constraints
• Gamma-ray halos around pulsars as the key to understanding cosmic ray transport in the Galaxy
• Constraints on the diffuse photon flux with energies above $10^{18}$ eV using the surface detector of the Telescope Array experiment
• HAWC J2227+610 and its association with G106.3+2.7, a new potential Galactic PeVatron
• Grand Unification Signal from Ultra High Energy Cosmic Rays?
• Modeling the Extragalactic Background Light and the Cosmic Star Formation History
• Cascade photons as test of protons in UHECR
• Constraints from Faraday rotation on the magnetic field structure in the Galactic halo
• 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
• UHECR Particle Spectra from Crypton Decays
• Turbulent axion-photon conversions in the Milky-Way
• Production and propagation of ultra-high energy photons using CRPropa 3
• Gas shells and magnetic fields in the Orion-Eridanus superbubble
• Probing Intergalactic Magnetic Fields with Simulations of Electromagnetic Cascades
• VHE gamma ray absorption by galactic interstellar radiation field
• Ultra-high energy Inverse Compton emission from Galactic electron accelerators
• Diffusive shock acceleration in radiation dominated environments
• Revisiting ultrahigh-energy constraints on decaying super-heavy dark matter
• Anisotropy test of the axion-like particle Universe opacity effect: a case for the Cherenkov Telescope Array
• Insights from LHAASO and IceCube into the origin of the Galactic diffuse TeV--PeV emission
• The TeV Sun Rises: Discovery of Gamma rays from the Quiescent Sun with HAWC
• Axion-Photon Conversion of LHAASO Multi-TeV and PeV Photons
• A pulsar wind nebula origin of the LHAASO-detected UHE gamma-ray sources
• First implications of Tibet AS${}_{\gamma }$ data for heavy dark matter
• Decomposing the Origin of TeV-PeV Emission from the Galactic Plane: Implications of Multi-messenger Observations
• Galactic PeVatrons and helping to find them: Effects of Galactic absorption on the observed spectra of very high energy $\gamma$-ray sources
• Galactic diffuse gamma-ray emission at TeV energy
• Solenoidal Improvements for the JF12 Galactic Magnetic Field Model
• An updated estimate of the cosmic radio background and implications for ultra-high-energy photon propagation
• Novel interpretation of the latest AMS-02 cosmic-ray electron spectrum
• The effect of triplet production on pair-Compton cascades in thermal radiation
• Towards discrimination between galactic and intergalactic axion-photon mixing
• The LHAASO PeVatron bright sky: what we learned
• Double Pair Production by Ultra High Energy Cosmic Ray Photons
• Ultra-high Energy Gamma-rays from Past Explosions in our Galaxy
• Detection prospects of very and ultra high-energy gamma rays from extended sources with ASTRI, CTA, and LHAASO
• Detection of a new molecular cloud in the LHAASO J2108+5157 region supporting a hadronic PeVatron scenario
• Expected LHAASO sensitivity to decaying dark matter signatures from dwarf galaxies gamma-ray emission
• Ultra-high energy neutrinos from high-redshift electromagnetic cascades
• Diffuse Galactic Gamma-rays from star clusters
• The prediction of using LHAASO's cosmic-ray electron measurements to constrain decaying heavy dark matter
• A gamma-ray study of galactic PeVatron candidates LHAASO J1825-1326 and LHAASO J1839-0545
• Neutrinos from muon-rich ultra high energy electromagnetic cascades: The MUNHECA code
• Predicting interstellar radiation fields from chemical evolution models

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• The GPSP Atlas: High-resolution Galactic Photon Survival Probability Atlas for Very-High- and Ultra-High-Energy Gamma-Ray Astronomy
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