English
Related papers

Related papers: Reconciling cosmic ray diffusion with Galactic mag…

200 papers

One of the unsolved problems in cosmic ray (CR) physics is the small radial gradient of the gamma-ray intensity compared to the inferred CR source distribution in the Galactic disk. In diffusive CR propagation models the most natural…

Astrophysics · Physics 2007-05-23 D. Breitschwerdt , V. Dogiel , H. J. V"olk

A crucial process in Galactic cosmic-ray (CR) transport is the spatial diffusion due to the interaction with the interstellar turbulent magnetic field. Usually, CR diffusion is assumed to be uniform and isotropic all across the Galaxy.…

High Energy Astrophysical Phenomena · Physics 2017-10-25 Silvio Sergio Cerri , Daniele Gaggero , Andrea Vittino , Carmelo Evoli , Dario Grasso

Cosmic ray propagation in the Galaxy is shortly reviewed. In particular we consider the self-consistent models of CR propagation. In these models CR streaming instability driven by CR anisotropy results in the Alfv\'enic turbulence which in…

High Energy Astrophysical Phenomena · Physics 2015-06-23 V. N. Zirakashvili

Galactic cosmic rays (CRs) play a crucial role in galaxy formation and evolution by altering gas dynamics and chemistry across multiple scales. Typical numerical simulations of CR transport assume a constant diffusion coefficient for the…

Astrophysics of Galaxies · Physics 2025-10-16 Sarah Thiele , Romain Teyssier

We have developed a model which aims to reproduce observational data of many kinds related to cosmic-ray (CR) origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron…

Astrophysics · Physics 2009-10-31 I. V. Moskalenko , A. W. Strong

The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Anvar Shukurov , Andrew Snodin , Amit Seta , Paul Bushby , Toby Wood

The spatial diffusion of energetic particles in a magnetic field composed of a large-scale background and a small-scale turbulent component should be expected to be anisotropic. While such anisotropic diffusion has been known for quite a…

High Energy Astrophysical Phenomena · Physics 2025-07-17 Julien Dörner , Jonas Hellrung , Julia Becker Tjus , Horst Fichtner

Determining the spatial distribution of Galactic cosmic rays (CRs) is fundamental to understand how these particles propagate in interstellar space and to infer their source spectra. The most sensitive method of studying this problem is…

High Energy Astrophysical Phenomena · Physics 2025-09-26 Paolo Lipari , Silvia Vernetto

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

Cosmic ray propagation is diffusive because of pitch angle scattering by waves. We demonstrate that if the high-amplitude magnetohydrodynamic turbulence with $\tilde B/\langle B\rangle \sim 1$ is present on top of the mean field gradient,…

High Energy Astrophysical Phenomena · Physics 2015-09-30 Mikhail V. Medvedev , Viktor V. Medvedev

The spatial distribution of cosmic ray (CR) particles in the interstellar medium (ISM) is of major importance in radio astronomy, where its knowledge is essential for the interpretation of observations, and in theoretical astrophysics,…

Astrophysics of Galaxies · Physics 2023-06-28 Devika Tharakkal , Andrew P. Snodin , Graeme R. Sarson , Anvar Shukurov

Under nonuniform convection, the distribution of diffusive particles can exhibit dipole and quadrupole anisotropy induced by the fluid inertial and shear force, respectively. These convection-related anisotropies, unlike the Compton-Getting…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Yiran Zhang , Siming Liu , Dejin Wu

We have studied the impact of cosmic-ray acceleration in SNR on the spectra of cosmic-ray nuclei in the Galaxy using a series expansion of the propagation equation, which allows us to use analytical solutions for part of the problem and an…

Astrophysics · Physics 2009-11-10 I. Buesching , A. Kopp , M. Pohl , R. Schlickeiser , C. Perrot , I. Grenier

Cosmic rays (CRs) generate diffuse emission while interacting with the Galactic magnetic field (B-field), the interstellar gas and the radiation field. This diffuse emission extends from radio, microwaves, through X-rays, to high-energy…

High Energy Astrophysical Phenomena · Physics 2016-06-22 Elena Orlando

Recent measurements of the cosmic ray (CR) antiproton flux have been shown to challenge existing CR propagation models. It was shown that the reacceleration models designed to match secondary to primary nuclei ratios (e.g., B/C) produce too…

Astrophysics · Physics 2010-05-27 I. V. Moskalenko , A. W. Strong , J. F. Ormes , S. G. Mashnik

A model is introduced, in which the irregularity spectrum of the Galactic magnetic field beyond the dissipation length scale is first a Kolmogorov spectrum $k^{-5/3}$ at small scales $\lambda \, = \, 2 \pi/k$ with $k$ the wave-number, then…

High Energy Astrophysical Phenomena · Physics 2015-11-16 P. L. Biermann , L. I. Caramete , A. Meli , B. N. Nath , E. -S. Seo , V. de Souza , J. Becker Tjus

Cosmic rays (CRs) have recently re-emerged as attractive candidates for mediating feedback in galaxies because of their long cooling timescales. They can have energy densities comparable to the thermal gas, but do not suffer catastrophic…

Astrophysics of Galaxies · Physics 2017-01-25 Joshua Wiener , Christoph Pfrommer , S. Peng Oh

The distribution of arrival directions of cosmic rays is remarkably isotropic, which is a consequence of their repeated scattering in magnetic fields. Yet, high-statistics observatories like IceCube and HAWC have revealed the presence of…

High Energy Astrophysical Phenomena · Physics 2019-12-04 Philipp Mertsch , Markus Ahlers

Constraining the behavior of cosmic ray data observed at Earth requires a precise understanding of how the cosmic rays propagate in the interstellar medium. The interstellar medium is not homogeneous; although turbulent magnetic fields…

High Energy Astrophysical Phenomena · Physics 2016-05-25 J. Patrick Harding , Chris L. Fryer , Susan Mendel

In a recent paper (Moskalenko et al., 2002), it has been shown that the flux of secondary cosmic ray (CR) antiprotons appears to be contradictory to measurements of secondary to primary nuclei ratios in cosmic rays when calculated in the…

Astrophysics · Physics 2010-05-27 V. S. Ptuskin , I. V. Moskalenko , F. C. Jones , A. W. Strong , S. G. Mashnik