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Related papers: The Diffuse Galactic Gamma-Ray Gradient

200 papers

Observations of the $\gamma$-ray emission around star clusters, isolated supernova remnants, and pulsar wind nebulae indicate that the cosmic-ray (CR) diffusion coefficient near acceleration sites can be suppressed by a large factor…

Astrophysics of Galaxies · Physics 2021-04-07 Vadim A. Semenov , Andrey V. Kravtsov , Damiano Caprioli

We investigate the interplay of cosmic ray (CR) propagation and advection in galaxy clusters. Propagation in form of CR diffusion and streaming tends to drive the CR radial profiles towards being flat, with equal CR number density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Torsten A. Ensslin , Christoph Pfrommer , Francesco Miniati , Kandaswamy Subramanian

Cosmic ray (CR) transport and acceleration is essential for many astrophysical problems, e.g., CMB foreground, ionization of molecular clouds and all high energy phenomena. Recent advances in MHD turbulence call for revisions in the…

High Energy Astrophysical Phenomena · Physics 2011-12-06 Huirong Yan , A. Lazarian

The GALPROP model for cosmic-ray (CR) propagation produces explicit predictions for the angular distribution of Galactic diffuse gamma rays. We compare our current models with EGRET spectra for various regions of the sky. This allows a…

Astrophysics · Physics 2007-05-23 A. W. Strong , I. V. Moskalenko , O. Reimer

Analyses of TeV-PeV cosmic ray (CR) diffusion around their sources usually assume either isotropic diffusion or anisotropic diffusion due to the regular Galactic magnetic field. We show that none of them are adequate on distances smaller…

High Energy Astrophysical Phenomena · Physics 2013-07-29 G. Giacinti , M. Kachelriess , D. V. Semikoz

Starburst galaxies are efficient $\gamma$-ray producers, because their high supernova rates generate copious cosmic ray (CR) protons, and their high gas densities act as thick targets off which these protons can produce neutral pions and…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Mark R. Krumholz , Roland M. Crocker , Siyao Xu , A. Lazarian , M. T. Rosevear , Jasper Bedwell-Wilson

Diffusive shock acceleration (DSA) is now widely accepted as the model to explain the production of cosmic rays (CRs) in a wide range of astrophysical environments. Despite initial successes of the theory in explaining the energetics and…

Astrophysics · Physics 2007-05-23 Hyesung Kang

Recent advances on gamma-ray observations from SuperNova Remnants and Molecular Clouds offer the possibility to study in detail the properties of the propagation of escaping Cosmic Rays (CR). However, a complete theory for CR transport…

High Energy Astrophysical Phenomena · Physics 2015-09-09 Lara Nava , Stefano Gabici , Alexandre Marcowith , Giovanni Morlino , Vladimir Ptuskin

The interaction of cosmic rays (CRs) with magnetic fields and the interstelar medium (ISM) leads to the production of nonthermal radiation. Although this has been a topic of study for many years, it still poses many challenges to the…

Cosmic rays (CRs) interact with turbulent magnetic fields in the intestellar medium, generating nonthermal emission. After many decades of studies, the theoretical understanding of their diffusion in the ISM continues to pose a challenge.…

High Energy Astrophysical Phenomena · Physics 2025-07-15 Lucas Barreto-Mota , Elisabete M. de Gouveia Dal Pino , Siyao Xu , Alexandre Lazarian

The arrival directions of Galactic cosmic rays (CRs) are highly isotropic. This is expected from the presence of turbulent magnetic fields in our Galactic environment that repeatedly scatter charged CRs during propagation. However, various…

High Energy Astrophysical Phenomena · Physics 2017-04-05 Markus Ahlers , Philipp Mertsch

The propagation of Galactic Cosmic Ray nuclei having energies between 100 MeV/nuc and several PeV/nuc is strongly believed to be of diffusive nature. The particles emitted by a source located in the disk do not pervade the whole Galaxy, but…

Astrophysics · Physics 2009-11-07 Richard Taillet , David Maurin

We present a novel interpretation of the $\gamma$-ray diffuse emission measured by Fermi-LAT and H.E.S.S. in the Galactic center (GC) region and the Galactic ridge (GR). In the first part we perform a data-driven analysis based on PASS8…

High Energy Astrophysical Phenomena · Physics 2017-07-26 D. Gaggero , D. Grasso , A. Marinelli , M. Taoso , A. Urbano

Recent observations of cosmic rays (CRs) have revealed a two-component anomaly in the spectra of primary and secondary particles, as well as their ratios, prompting investigation into their common origin. In this study, we incorporate the…

High Energy Astrophysical Phenomena · Physics 2024-03-08 Yu-Hua Yao , Xu-Lin Dong , Yi-Qing Guo , Qiang Yuan

Cosmic-ray transport in astrophysical environments is often dominated by the diffusion of particles in a magnetic field composed of both a turbulent and a mean component. This process, which is two-fold turbulent mixing in that the particle…

High Energy Astrophysical Phenomena · Physics 2021-12-14 P. Reichherzer , L. Merten , J. Dörner , J. Becker Tjus , M. J. Pueschel , E. G. Zweibel

The diffuse gamma-ray background radiation (GBR) at high Galactic latitudes could be dominated by inverse Compton scattering (ICS) of cosmic ray (CR) electrons on the cosmic microwave background radiation (CBR) and on starlight (SL) in an…

Astrophysics · Physics 2007-05-23 Arnon Dar

An extensive program for the calculation of galactic cosmic-ray propagation has been developed. Primary and secondary nucleons, primary and secondary electrons, secondary positrons and antiprotons are included. Fragmentation and energy…

Astrophysics · Physics 2007-05-23 A. W. Strong , I. V. Moskalenko

The physics of Cosmic ray (CR) transport remains a key uncertainty in assessing whether CRs can produce galaxy-scale outflows consistent with observations. In this paper, we elucidate the physics of CR-driven galactic winds for CR transport…

Astrophysics of Galaxies · Physics 2021-11-24 Eliot Quataert , Todd A. Thompson , Yan-Fei Jiang

A self-consistent model of a one-dimensional cosmic-ray (CR) halo around the Galactic disk is formulated with the restriction to a minimum number of free parameters. It is demonstrated that the turbulent cascade of MHD waves does not…

High Energy Astrophysical Phenomena · Physics 2020-11-18 V. A. Dogiel , A. V. Ivlev , D. O. Chernyshov , C. -M. Ko

We argue that the diffusion of cosmic rays in the Galactic magnetic field has to be strongly anisotropic. As a result, the number of CR sources contributing to the local CR flux is reduced by a factor $\sim 200$. The CR density is therefore…

High Energy Astrophysical Phenomena · Physics 2019-05-22 M. Kachelriess