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Related papers: Explaining TeV Cosmic-Ray Anisotropies with Non-Di…

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Interpretations of synchrotron observations often assume a tight correlation between magnetic and cosmic ray energy densities. We examine this assumption using both test-particle simulations of cosmic rays and MHD simulations which include…

Astrophysics of Galaxies · Physics 2018-10-10 Amit Seta , Anvar Shukurov , Paul J. Bushby , Toby S. Wood

We consider the propagation of galactic cosmic rays under assumption that the interstellar medium is a fractal one. An anomalous diffusion equation in terms of fractional derivatives is used to describe of cosmic ray propagation. The…

Astrophysics · Physics 2007-05-23 A. A. Lagutin , V. V. Uchaikin

Since the universe is not transparent to gamma rays with energies above around one hundred GeV, it is necessary to account for the interaction of high-energy photons with intergalactic radiation fields in order to model gamma-ray…

High Energy Astrophysical Phenomena · Physics 2025-05-16 Antonio Capanema , Carlos Blanco

Simulations of the cosmic-ray (CR) anisotropy down to TeV energies are presented, using turbulence parameters consistent with those inferred from observations of the interstellar medium. We compute the angular power spectra $C_{\ell}$ of…

High Energy Astrophysical Phenomena · Physics 2024-10-15 Wenyi Bian , Gwenael Giacinti , Brian Reville

We study the nonlinear growth of kinetic gyroresonance instability of cosmic rays (CRs) induced by large scale compressible turbulence. This feedback of cosmic rays on turbulence was shown to induce an important scattering mechanism in…

High Energy Astrophysical Phenomena · Physics 2011-03-28 Huirong Yan , A. Lazarian

Detecting and characterizing the anisotropy pattern of the arrival directions of the highest energy cosmic rays are crucial steps towards the identification of their sources. We discuss a possible distortion of the cosmic ray flux induced…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Sihem Kalli , Martin Lemoine , Kumiko Kotera

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-ray scattering on magnetic turbulence leads to spatial diffusive propagation; if the scattering medium is moving, this will inevitably also cause changes in the momentum of the particles, so-called diffusive reacceleration. This can…

High Energy Astrophysical Phenomena · Physics 2015-08-12 Luke O'C. Drury , Andrew W. Strong

Identifying the sources of the highest energy cosmic rays requires understanding how they are deflected by the stochastic, spatially intermittent intergalactic magnetic field. Here we report measurements of energetic charged-particle…

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

Before being detected at Earth, charged cosmic rays propagate across the Solar System and undergo interactions with the turbulent solar wind and with the heliospheric magnetic field. As a result, they are subject to a series of processes…

High Energy Astrophysical Phenomena · Physics 2018-11-08 Andrea Vittino , Carmelo Evoli , Daniele Gaggero

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

Cosmic ray propagation in the Milky Way and other galaxies is largely diffusive, with mean free path determined primarily by pitch angle scattering from hydromagnetic waves with wavelength of order the cosmic ray gyroradius. In the theory…

High Energy Astrophysical Phenomena · Physics 2020-02-19 Ellen G. Zweibel

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

Latest precise cosmic-ray (CR) measurements and present gamma-ray observations have started challenging our understanding of CR transport and interaction in the Galaxy. Moreover, because the density of CRs is similar to the density of the…

From the analysis of AGASA data above $4 \times 10^{19}$ eV, we show that the ultra-high energy cosmic rays flux is neither purely isotropic, nor reflects the expected anisotropy from a pure source distribution that maps large scale…

Astrophysics · Physics 2009-10-31 Gustavo Medina-Tanco

The bulk of the diffuse galactic gamma-ray emission above a few tens of GeV has been conventionally ascribed to the decay of neutral pions produced in cosmic-ray interactions with interstellar matter. Cosmic-ray electrons may, however, make…

Astrophysics · Physics 2008-11-26 T. A. Porter , R. J. Protheroe

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

I review what is known and surmised about magnetic fields in space, from our Milky Way environment to the distant Universe beyond the GZK horizon. This includes our gradually improving specification of the CR propagation environment within…

High Energy Astrophysical Phenomena · Physics 2015-03-17 Philipp P. Kronberg

We analyze DAMPE and H.E.S.S. measurements of the total cosmic-ray electron-positron spectrum, together with the AMS-02 positron fraction, using an anisotropic, spatially varying diffusion framework. The diffusion-tensor components are…

High Energy Astrophysical Phenomena · Physics 2026-04-27 V. D. Borisov , I. A. Kudryashov