Ultrahigh-energy diffuse gamma-ray emission from cosmic-ray interactions with medium surrounding acceleration sources

Abstract

The diffuse $\gamma$-ray spectrum at sub-PeV energy region has been measured for the first time by the Tibet-AS$\gamma$ experiment. It will shed new light on the understanding of origin and propagation of Galactic cosmic rays at very high energies. It has been pointed out that the traditional cosmic ray propagation model based on low energy measurements undershoot the new data, and modifications of the model with new ingredients or alternative propagation framework is required. In this work, we propose that the hadronic interactions between freshly accelerated cosmic rays and the medium surrounding the sources, which was neglected in the traditional model, can naturally account for the Tibet-AS$\gamma$ diffuse emission. We show that this scenario gives a consistent description of other secondary species such as the positron spectrum, the boron-to-carbon ratio, and the antiproton-to-proton ratio. As a result, the electron spectrum above 10 TeV will have a hardening due to this secondary component, which may be tested by future measurements.

arXiv comment9 pages, 4 figures

References in corpus (52)

• Cosmic-ray propagation and interactions in the Galaxy
• Fermi-LAT Observations of the Diffuse Gamma-Ray Emission: Implications for Cosmic Rays and the Interstellar Medium
• Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons
• Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth
• Diffuse Galactic continuum gamma rays. A model compatible with EGRET data and cosmic-ray measurements
• On the knee in the energy spectrum of cosmic rays
• Development of the Model of Galactic Interstellar Emission for Standard Point-Source Analysis of Fermi Large Area Telescope Data
• Proton and Helium Spectra from the CREAM-III Flight
• Spectral breaks as a signature of cosmic ray induced turbulence in the Galaxy
• First Detection of sub-PeV Diffuse Gamma Rays from the Galactic Disk: Evidence for Ubiquitous Galactic Cosmic Rays beyond PeV Energies
• Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy
• Cosmic-ray propagation with DRAGON2: I. numerical solver and astrophysical ingredients
• Origin of the Cosmic Ray Spectral Hardening
• A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro
• Measurement of the cosmic ray helium energy spectrum from 70 GeV to 80 TeV with the DAMPE space mission
• Interpretation of AMS-02 electrons and positrons data
• Astrophysical models for the origin of the positron "excess"
• Radial distribution of the diffuse gamma-ray emissivity in the galactic disk
• Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622 + 3749 Observed by LHAASO-KM2A
• Bayesian analysis of spatial-dependent cosmic-ray propagation: astrophysical background of antiprotons and positrons
• Cosmic-ray protons, nuclei, electrons, and antiparticles under a two-halo scenario of diffusive propagation
• Study of the diffuse gamma-ray emission from the Galactic plane with ARGO-YBJ
• Pulsar interpretation for the AMS-02 result
• Spatial-Dependent Diffusion of Cosmic Rays and the Ratio of pbar/p, B/C
• Understanding the spectral hardenings and radial distribution of Galactic cosmic rays and Fermi diffuse gamma-rays with spatially-dependent propagation
• Cosmic-Ray Electron Excess from Pulsars is Spiky or Smooth?: Continuous and Multiple Electron/Positron injections
• Excesses of Cosmic Ray Spectra from A Single Nearby Source
• Gamma rays as probes of cosmic-ray propagation and interactions in galaxies
• Indication of nearby source signatures of cosmic rays from energy spectra and anisotropies
• Explanation of the knee-like feature in the DAMPE cosmic $e^{-}+e^{+}$ energy spectrum
• Revisiting Spatial-Dependent Propagation Model with Latest Observations of Cosmic Ray Nuclei
• Cosmic ray electrons and positrons from discrete stochastic sources
• Antiprotons from dark matter annihilation through light mediators and a possible excess in AMS-02 $\bar{p}/p$ data
• Dark Matter Particle Explorer observations of high-energy cosmic ray electrons plus positrons and their physical implications
• Observation of photons above 300 TeV associated with a high-energy neutrino from the Cygnus region
• VHE gamma ray absorption by galactic interstellar radiation field
• Variance of the Galactic nuclei cosmic ray flux
• Anisotropies of different mass compositions of cosmic rays
• Nearby source interpretation of differences among light and medium composition spectra in cosmic rays
• Perspective on the cosmic-ray electron spectrum above TeV
• Light Speed Variation in a String Theory Model for Space-Time Foam
• Origin of Galactic sub-PeV diffuse gamma-ray emission: Constraints from high-energy neutrino observations
• A systematic study on the cosmic ray antiproton flux
• First implications of Tibet AS${}_{\gamma }$ data for heavy dark matter
• Magnetically Arrested Disks in Quiescent Black-Hole Binaries: Formation Scenario, Observable Signatures, and Potential PeVatrons
• Pion decay model of TIBET-AS$\gamma$ PeV gamma-ray signal
• Interpretation of the excess of antiparticles within a modified paradigm of galactic cosmic rays
• On the Contribution of "Fresh" Cosmic Rays to the Excesses of Secondary Particles
• Electron and positron spectra in the three dimensional spatial-dependent propagation model
• Galactic diffuse gamma rays --- recalculation based on the new measurements of cosmic electron spectrum
• Possible bump structure of cosmic ray electrons unveiled by AMS-02 data and its common origin along with the nuclei and positron
• The diffuse GeV-TeV $\gamma$-ray emission of the Cygnus region

Cited by in corpus (8)

• Measurement of ultra-high-energy diffuse gamma-ray emission of the Galactic plane from 10 TeV to 1 PeV with LHAASO-KM2A
• Explaining the GeV antiproton/$\gamma -$ray excesses and W-boson mass anomaly in an inert two Higgs doublet model
• Galactic diffuse gamma-ray emission from GeV to PeV energies in light of up-to-date cosmic ray measurements
• Insights from LHAASO and IceCube into the origin of the Galactic diffuse TeV--PeV emission
• Measurement of Very-high-energy Diffuse Gamma-ray Emissions from the Galactic Plane with LHAASO-WCDA
• Interpretations of the cosmic ray secondary-to-primary ratios measured by DAMPE
• Evidence of fresh cosmic ray in galactic plane based on DAMPE measurement of B/C and B/O ratios
• Cosmic-ray deuteron excess from a primary component