Diffuse Gamma Rays in 3D Galactic Cosmic-ray Propagation Models
arXiv:1701.07285 · doi:10.1063/1.4969008
Abstract
The Picard code for the numerical solution of the Galactic cosmic ray propagation problem allows for high-resolution models that acknowledge the 3D structure of our Galaxy. Picard was used to determine diffuse gamma-ray emission of the Galaxy over the energy range from 100 MeV to 100 TeV. We discuss the impact of a cosmic-ray source distribution aligned with the Galactic spiral arms for a range of such spiral-arm models. As expected, the impact on the gamma-ray emission is most distinct in the inverse-Compton channel, where imprints of the spiral arms are visible and yield predictions that are no longer symmetric to the rotational axis of the Milkyway. We will illustrate these differences by a direct comparison to results from previous axially symmetric Galactic propagation models: we find differences in the gamma-ray flux both on global scales and on local scales related to the spiral arm tangents. We compare gamma-ray flux and spectra at on-arm vs. off-arm projections and characterize the differences to axially symmetric models.
References in corpus (18)
- Diffuse continuum gamma rays from the Galaxy
- A New Model of the Galactic Magnetic Field
- The H.E.S.S. survey of the Inner Galaxy in very high-energy gamma-rays
- 2FHL: The Second Catalog of Hard Fermi-LAT Sources
- Inverse Compton Origin of the Hard X-Ray and Soft Gamma-Ray Emission from the Galactic Ridge
- The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
- PICARD: A novel code for the Galactic Cosmic Ray propagation problem
- Three-Dimensional Model of Cosmic-Ray Lepton Propagation Reproduces Data from the Alpha Magnetic Spectrometer on the International Space Station
- 3D Distribution of Molecular Gas in the Barred Milky Way
- A common solution to the cosmic ray anisotropy and gradient problems
- Catalog of observed tangents to the spiral arms in the Milky Way galaxy
- Anisotropic diffusion of galactic cosmic ray protons and their steady-state azimuthal distribution
- Analytical models of X-shape magnetic fields in galactic halos
- Spiral Arms as Cosmic Ray Source Distributions
- Propagation in 3D spiral-arm cosmic-ray source distribution models and secondary particle production using PICARD
- A Generalized Diffusion Tensor for Fully Anisotropic Diffusion of Energetic Particles in the Heliospheric Magnetic Field
- Recovering the observed B/C ratio in a dynamic spiral-armed cosmic ray model
- Radiation fields in star-forming galaxies: the disk, thin disk and bulge
Cited by in corpus (5)
- A deep spectromorphological study of the -ray emission surrounding the young massive stellar cluster Westerlund 1
- Gamma rays as probes of cosmic-ray propagation and interactions in galaxies
- New determination of the production cross section for rays in the Galaxy
- Weighing the Local Interstellar Medium using Gamma Rays and Dust
- Modulation of the galactic cosmic ray spectrum in an anisotropic diffusion approach