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Related papers: Global diffusion of cosmic rays

200 papers

We present a Monte-Carlo (MC) calculation of the propagation of cosmic ray protons in the Galaxy for energies above 1 PeV. We discuss the relative strengths of competing effects such as parallel/perpendicular diffusion and drifts in toy…

Astrophysics · Physics 2007-05-23 Daniel De Marco , Pasquale Blasi , Todor Stanev

In a weakly ionized plasma, the evolution of the magnetic field is described by a "generalized Ohm's law" that includes the Hall effect and the ambipolar diffusion terms. These terms introduce additional spatial and time scales which play a…

Solar and Stellar Astrophysics · Physics 2009-11-13 V. Krishan , Z. Yoshida

The Cosmic Rays propagation was studied in details using the HelMod-2D Monte Carlo code, that includes a general description of the diffusion tensor, and polar magnetic-field. The Numerical Approach used in this work is based on a set of…

Earth and Planetary Astrophysics · Physics 2013-07-22 P. Bobik , G. Boella , M. J. Boschini , S. Della Torre , M. Gervasi , D. Grandi , G. La Vacca , K. Kudela , S. Pensotti , P. G. Rancoita , D. Rozza , M. Tacconi

The transport of non-thermal particles across a large-scale magnetic field in the presence of magnetised turbulence has been a long-standing issue in high-energy astrophysics. Of particular interest is the dependence of the parallel and…

High Energy Astrophysical Phenomena · Physics 2025-10-03 Marco Kuhlen , Vo Hong Minh Phan , Philipp Mertsch

Current particle transport models describe the propagation of charged particles across the mean field direction in turbulent plasmas as diffusion. However, recent studies suggest that at short time-scales, such as soon after solar energetic…

Solar and Stellar Astrophysics · Physics 2017-01-18 T. Laitinen , S. Dalla

We describe a method for the numerical computation of the propagation of primary and secondary nucleons, primary electrons, and secondary positrons and electrons. Fragmentation and energy losses are computed using realistic distributions…

Astrophysics · Physics 2011-05-05 A. W. Strong , I. V. Moskalenko

We model the transport of cosmic ray nuclei in the Galaxy by means of a new numerical code. Differently from previous numerical models we account for a generic spatial distribution of the diffusion coefficient. We found that in the case of…

Astrophysics · Physics 2016-05-19 C. Evoli , D. Gaggero , D. Grasso , L. Maccione

Galactic cosmic rays (CRs) are a fundamental non-thermal component of the interstellar medium (ISM). Understanding the transport of super-high-energy particles is essential for interpreting observations of Galactic PeVatrons. Classical…

High Energy Astrophysical Phenomena · Physics 2026-04-07 Yue Hu

Particle transport, acceleration and energisation are phenomena of major importance for both space and laboratory plasmas. Despite years of study, an accurate theoretical description of these effects is still lacking. Validating models with…

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

Energetic particle transport in a finite amplitude magnetosonic and Alfvenic turbulence is considered using Monte Carlo particle simulations, which involve an integration of particle equation of motion. We show that in a low-Betha plasma…

Astrophysics · Physics 2008-02-03 G. Michalek , M. Ostrowski , R. Schlickeiser

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

We take a phenomenological approach in a minimal model to understand the spectral intensity of secondary cosmic-ray particles like positrons, antiprotons, Lithium, Beryllium and Boron. Our analysis shows that cosmic rays at $\sim$ GeV…

High Energy Astrophysical Phenomena · Physics 2023-09-13 Ramanath Cowsik , Dawson Huth

The spatial diffusion of cosmic rays in turbulent magnetic fields can, in the most general case, be fully anisotropic, i.e. one has to distinguish three diffusion axes in a local, field-aligned frame. We reexamine the transformation for the…

An extensive program for the calculation of galactic cosmic-ray propagation has been developed. This is a continuation of the work described in Strong & Youssefi (1995). The main motivation for developing this code is the prediction of…

Astrophysics · Physics 2009-10-30 A. W. Strong , I. V. Moskalenko

Propagation of cosmic rays (CRs) in turbulent and magnetized astrophysical media is a long-standing problem that requires both understanding of the properties of turbulent magnetic fields and their interaction with energetic particles. This…

Astrophysics of Galaxies · Physics 2023-04-07 Alex Lazarian , Siyao Xu , Yue Hu

Recent direct measurements of Galactic cosmic ray spectra by balloon/space-borne detectors reveal spectral hardenings of all major nucleus species at rigidities of a few hundred GV. The all-sky diffuse gamma-ray emissions measured by the…

High Energy Astrophysical Phenomena · Physics 2018-03-21 Yi-Qing Guo , Qiang Yuan

(abridged) Within nearby galaxies, variations in the radio-FIR correlation have been observed, mainly because the cosmic ray electrons migrate before they lose their energy via synchrotron emission or escape. The major cosmic ray electron…

Astrophysics of Galaxies · Physics 2020-02-05 B. Vollmer , M. Soida , R. Beck , M. Powalka

We introduce a novel diffusion model for the propagation of cosmic rays (CRs) that incorporates an anisotropic diffusion tensor of a general form within a realistically modeled large-scale Galactic magnetic field. The parameters of the…

High Energy Astrophysical Phenomena · Physics 2025-07-22 V. D. Borisov , V. O. Yurovsky , I. A. Kudryashov

There is a growing set of observational data demonstrating that cosmic rays exhibit small-scale anisotropies (5-30 deg) with amplitude deviations lying between 0.01-0.1 percent that of the average cosmic ray flux. A broad range of models…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Margot Fitz Axen , Julia Speicher , Aimee Hungerford , Chris L. Fryer