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Related papers: Acceleration in a Periodic Magnetic Field

200 papers

We study of the effect of turbulence on diffusion processes within magnetized medium. While we exemplify our treatment with heat transfer processes, our results are quite general and are applicable to different processes, e.g. diffusion of…

Astrophysics · Physics 2008-11-26 Alex Lazarian

Diffusion of particles in velocity space undergoing turbulent field was extensively studied in the problem of warm beam relaxation. Under low field intensities the diffusion is described by the Fokker-Planck equation with the diffusion…

Plasma Physics · Physics 2007-05-23 Anatoly Zagorodny , Volodymyr Zasenko , Jan Weiland

Here we investigate some aspects of stochastic acceleration of ultrarelativistic electrons by magnetic turbulence. In particular, we discuss the steady-state energy spectra of particles undergoing momentum diffusion due to resonant…

Astrophysics · Physics 2009-11-13 L. Stawarz , V. Petrosian

Counterpropagating Alfv\'en waves are ubiquitously observed in many astrophysical environments, such as a star surface and a planetary foreshock. We discuss an efficient particle acceleration mechanism in two counterpropagating circularly…

High Energy Astrophysical Phenomena · Physics 2023-04-06 S. Isayama , K. Takahashi , S. Matsukiyo , T. Sano

The theory of diffusive acceleration of energetic particles at shock fronts assumes charged particles undergo spatial diffusion in a uniform magnetic field. If, however, the magnetic field is not uniform, but has a stochastic or braided…

Astrophysics · Physics 2007-05-23 J. G. Kirk , P. Duffy , Y. A. Gallant

Particle-In-Cell (kinetic) simulations of shear Alfv\'en wave interaction with one dimensional, across the uniform magnetic field, density inhomogeneity (phase mixing) in collisionless plasma were performed for the first time. As a result a…

Astrophysics · Physics 2009-11-10 David Tsiklauri , Jun-Ichi Sakai , Shinji Saito

We expand the off-resonant scattering theory for particle diffusion in magnetized current filaments that can be typically compared to astrophysical jets, including active galactic nucleus jets. In a high plasma beta region where the…

Astrophysics · Physics 2009-11-13 Mitsuru Honda , Yasuko S. Honda

The propagation of shear Alfven wave packets in inhomogeneous magnetic fields, at the origin of their distortion, regardless of the occurrence of non-linear coupling, is considered. It is shown that the distortion mechanism can be regarded…

Astrophysics · Physics 2008-10-23 Nicolas Bian , David Tsiklauri

We investigate the impact of magnetic fields and diffusion mechanisms on the energy spectra of particles accelerated via diffusive shock acceleration. We analyse magnetised shock jump conditions and demonstrate how magnetisation and angular…

High Energy Astrophysical Phenomena · Physics 2026-01-01 Anshuman Verma , Saksham Chandna , Divyansh Tripathi , Ritam Mallick

Plasma flow and acceleration in the converging-diverging magnetic field configuration, such as magnetic nozzle in electric propulsion and open magnetic mirrors for fusion applications are considered. This work analyses plasma acceleration…

Plasma Physics · Physics 2025-06-25 A. I. Smolyakov , A. Sabo , S. I. Krasheninnikov , P. N. Yushmanov

The investigation of the diffusive transport of charged particles in a turbulent magnetic field remains a subject of considerable interest. Research has most frequently concentrated on determining the diffusion coefficient in the presence…

The ubiquitous turbulence in astrophysical plasmas is important for both magnetic reconnection and reconnection acceleration. We study the particle acceleration during fast 3D turbulent reconnection with reconnection-driven turbulence.…

Plasma Physics · Physics 2023-01-11 Siyao Xu , Alex Lazarian

Nonthermal acceleration of particles in magnetohydrodynamic (MHD) turbulence plays a central role in a wide variety of astrophysical sites. This physics is addressed here in the context of a strong turbulence, composed of coherent…

High Energy Astrophysical Phenomena · Physics 2021-10-06 Martin Lemoine

We present a theory for the generation of mesoscale ($kr_{g}\ll 1$, where $r_{g}$ is the cosmic ray gyroradius) magnetic fields during diffusive shock acceleration. The decay or modulational instability of resonantly excited Alfven waves…

Astrophysics · Physics 2008-11-26 P. H. Diamond , M. A. Malkov

We demonstrate that particles are regularly accelerated while experiencing curvature drift in flows driven by magnetic tension. Some examples of such flows include spontaneous turbulent reconnection and decaying magnetohydrodynamic (MHD)…

High Energy Astrophysical Phenomena · Physics 2016-03-04 Andrey Beresnyak , Hui Li

Particles ejected from the Sun that stream through the surrounding plasma of the solar wind are causing instabilities. These generate wavemodes in a certain frequency range especially within shock regions, where particles are accelerated.…

Solar and Stellar Astrophysics · Physics 2015-06-11 Sebastian Lange , Felix Spanier

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

Astrophysics of Galaxies · Physics 2012-12-17 R. Santos-Lima , A. Lazarian , E. M. de Gouveia Dal Pino , J. Cho

Non-helical hydromagnetic turbulence with an externally imposed magnetic field is investigated using direct numerical simulations. It is shown that the imposed magnetic field lowers the spectral magnetic energy in the inertial range. This…

Astrophysics · Physics 2007-05-23 Nils Erland L. Haugen , Axel Brandenburg

Magnetohydrodynamic (MHD) turbulence is an important agent of energetic particle acceleration. Focusing on the compressible properties of magnetic turbulence, we adopt test particle method to study the particle acceleration from Alfv\'en,…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Jianfu Zhang , Fuyuan Xiang

Intercluster medium is expected to be turbulent with turbulence being superAlfvenic at large scales. Magnetic fields substantially modify the turbulent cascade when the turbulence reaches the scales at which the fluctuation velocity gets…

Astrophysics · Physics 2009-11-11 A. Lazarian