English
Related papers

Related papers: Simulating field-aligned diffusion of a cosmic ray…

200 papers

The evolution of magnetic fields in galaxies is still an open problem in astrophysics. In nearby galaxies the far-infrared-radio correlation indicates the coupling between magnetic fields and star formation. The correlation arises from the…

Astrophysics of Galaxies · Physics 2015-06-19 Jennifer Schober , Dominik R. G. Schleicher , Ralf S. Klessen

We review numerical methods for simulations of cosmic ray (CR) propagation on galactic and larger scales. We present the development of algorithms designed for phenomenological and self-consistent models of CR propagation in kinetic…

High Energy Astrophysical Phenomena · Physics 2021-06-17 M. Hanasz , A. Strong , P. Girichidis

Nowadays, the calculation of the Galactic Cosmic Rays diffusion coefficient with direct microscopic numerical simulations is a widespread approach. In this work, we investigated the numerical limits for such calculations and demonstrated…

Instrumentation and Methods for Astrophysics · Physics 2026-05-14 Vladimir Yurovsky , Ilya Kudryashov

Recent studies have shown that the anisotropy is of great value to decipher cosmic rays' origin and propagation. We have built an unified scenario to describe the observations of the energy spectra and the large-scale anisotropy and called…

High Energy Astrophysical Phenomena · Physics 2024-02-29 Ai-feng Li , Qiang Yuan , Wei Liu , Yi-qing Guo

Cosmic rays (CRs) leave their sources mainly along the local magnetic field; in doing so they excite both resonant and nonresonant modes through streaming instabilities. The excitation of these modes leads to enhanced scattering and in turn…

High Energy Astrophysical Phenomena · Physics 2021-06-10 Benedikt Schroer , Oreste Pezzi , Damiano Caprioli , Colby Haggerty , Pasquale Blasi

There is an observational correlation between astrophysical shocks and non-thermal particle distributions extending to high energies. As a first step toward investigating the possible feedback of these particles on the shock at the…

High Energy Astrophysical Phenomena · Physics 2012-01-31 Thomas Stroman , Martin Pohl , Jacek Niemiec , Antoine Bret

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 consider the possibility that cosmic magnetic field, instead of being uniformly distributed, is strongly correlated with the large scale structure of the universe. Then, the observed rotational measure of extra-galactic radio sources…

Astrophysics · Physics 2011-07-19 Dongsu Ryu , Hyesung Kang , Peter L. Biermann

The propagation of cosmic rays can be described as a diffusive motion in most galactic environments. High-energy gamma-rays measured by Fermi have allowed inference of a gradient in the cosmic-ray density and spectral energy behavior in the…

High Energy Astrophysical Phenomena · Physics 2021-10-14 J. Dörner , P. Reichherzer , L. Merten , J. Becker Tjus , H. Fichtner , M. J. Pueschel , E. G. Zweibel

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for substantial revisions in our understanding of cosmic ray transport. In this paper we use gyroresonance recently obtained scaling laws for MHD modes to…

Astrophysics · Physics 2009-11-07 Huirong Yan , A. Lazarian

A detailed understanding of cosmic-ray transport in galactic halos is essential for explaining various observations, such as the radio continuum measurements of synchrotron radiation from energetic electrons. Of central importance is the…

Astrophysics of Galaxies · Physics 2025-07-14 J. Kleimann , H. Fichtner , M. Stein , R. -J. Dettmar , D. J. Bomans , S. Oughton

We consider the propagation of galactic cosmic rays in the fractal interstellar medium. Steady state solution of the fractional diffusion equation, describing cosmic ray propagation, is found. We show that the exponent of the steady state…

Astrophysics · Physics 2007-05-23 A. A. Lagutin , V. V. Makarov , A. G. Tyumentsev

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 transport of cosmic rays (CRs) is crucial for the understanding of almost all high-energy phenomena. Both pre-existing large-scale magnetohydrodynamic (MHD) turbulence and locally generated turbulence through plasma instabilities are…

High Energy Astrophysical Phenomena · Physics 2018-02-28 Olga Lebiga , Reinaldo Santos-Lima , Huirong Yan

Cosmic rays scatter off magnetic irregularities (Alfven waves) with which they are resonant, that is waves of wavelength comparable to their gyroradii. These waves may be generated either by the cosmic rays themselves, if they stream faster…

Astrophysics · Physics 2009-11-10 Alison J. Farmer , Peter Goldreich

The flux of ultrahigh energy cosmic rays reaching the Earth is affected by the interactions with the cosmic radiation backgrounds as well as with the magnetic fields that are present along their trajectories. We combine the SimProp cosmic…

High Energy Astrophysical Phenomena · Physics 2021-09-08 Juan Manuel González , Silvia Mollerach , Esteban Roulet

We study the impact of possible spiral-arm distributions of Galactic cosmic-ray sources on the flux of various cosmic-ray nuclei throughout our Galaxy. We investigate model cosmic-ray spectra at the nominal position of the sun and at…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Ralf Kissmann , Michael Werner , Olaf Reimer , Andrew W. Strong

The diffusion of astrophysical magnetic fields in conducting fluids in the presence of turbulence depends on whether magnetic fields can change their topology or reconnect in highly conducting media. Recent progress in understanding fast…

Astrophysics of Galaxies · Physics 2010-03-16 A. Lazarian , R. Santos-Lima , E. Gouveia Dal Pino

More and more observations have indicated the existence of slow diffusion phenomena in astrophysical environments, such as around the supernova remnants and pulsar $\gamma$-ray halos, where the diffusion coefficient of cosmic rays (CRs)…

High Energy Astrophysical Phenomena · Physics 2025-06-24 Yawen Xiao , Jianfu Zhang , Siyao Xu

The process of diffusive shock acceleration relies on the efficacy with which hydromagnetic waves can scatter charged particles in the precursor of a shock. The growth of self-generated waves is driven by both resonant and non-resonant…

Astrophysics · Physics 2009-11-13 B. Reville , S. O'Sullivan , P. Duffy , J. G. Kirk