English
Related papers

Related papers: Particle Acceleration in Turbulence and Weakly Sto…

200 papers

First-order Fermi acceleration processes at ultrarelativistic shocks are studied with Monte Carlo simulations. The accelerated particle spectra are obtained by integrating the exact particle trajectories in a turbulent magnetic field near…

Astrophysics · Physics 2009-11-13 Jacek Niemiec

A box model is used to study first order Fermi acceleration driven by magnetic reconnection. It is shown, at least in this simple model, that the spectral index of the accelerated particles is related to the total compression in the same…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Luke O'C. Drury

This proceedings paper reports on the theoretical modelling of particle acceleration in magnetised turbulent plasmas. It briefly reviews some recent findings obtained from fully kinetic numerical simulations of large-amplitude, semi to…

High Energy Astrophysical Phenomena · Physics 2025-12-18 M. Lemoine

In this paper we investigate a situation where relativistic particles are reaccelerated diffusing across regions of reconnection and magnetic dynamo in super-Alfvenic, incompressible large-scale turbulence. We present an exploratory study…

High Energy Astrophysical Phenomena · Physics 2016-03-23 G. Brunetti , A. Lazarian

Magnetized turbulence and magnetic reconnection are often invoked to explain the nonthermal emission observed from a wide variety of astrophysical sources. By means of fully-kinetic 2D and 3D PIC simulations, we investigate the interplay…

High Energy Astrophysical Phenomena · Physics 2019-12-04 Luca Comisso , Lorenzo Sironi

Using fully kinetic simulations, we demonstrate that magnetic reconnection in relativistic plasmas is highly efficient at accelerating particles through a first-order Fermi process resulting from the curvature drift of particles in the…

High Energy Astrophysical Phenomena · Physics 2014-10-16 Fan Guo , Hui Li , William Daughton , Yi-Hsin Liu

The aim of this work is to investigate and characterise particle behaviour in a 3D magnetohydrodynamic (MHD) model of a reconnecting magnetic separator. We use a relativistic guiding-centre test-particle code to investigate electron and…

Solar and Stellar Astrophysics · Physics 2015-12-23 J. Threlfall , J. E. H. Stevenson , C. E. Parnell , T. Neukirch

The theory of first order Fermi acceleration at shocks assumes that particles diffuse due to scattering off slow-moving magnetic irregularities. However, cosmic rays are closely tied to magnetic field lines, and the transport process,…

Astrophysics · Physics 2011-05-23 P. Duffy , J. G. Kirk , Y. A. Gallant , R. O. Dendy

We review the basic concepts of magnetic reconnection and propose a general framework for the astrophysical reconnection at large scales. Magnetic reconnection is the rearrangement of magnetic field topology. The conventional Sweet-Parker…

High Energy Astrophysical Phenomena · Physics 2018-06-18 Amir Jafari , Ethan Vishniac

Magnetic reconnection, especially in the relativistic regime, provides an efficient mechanism for accelerating relativistic particles and thus offers an attractive physical explanation for nonthermal high-energy emission from various…

High Energy Astrophysical Phenomena · Physics 2022-07-15 Dmitri A. Uzdensky

Magnetic reconnection in the relativistic regime has been proposed as an important process for the efficient production of nonthermal particles and high-energy emissions. Using fully kinetic particle-in-cell simulations, we investigate how…

High Energy Astrophysical Phenomena · Physics 2023-05-10 Omar French , Fan Guo , Qile Zhang , Dmitri Uzdensky

Magnetohydrodynamic (MHD) turbulence is a ubiquitous dynamical state of astrophysical plasmas and a primary agent in the redistribution, dissipation, and conversion of energy into particle populations. Yet turbulence is still most often…

High Energy Astrophysical Phenomena · Physics 2026-04-21 Loukas Vlahos

Magnetic reconnection occurs ubiquitously in the universe and is often invoked to explain fast energy release and particle acceleration in high-energy astrophysics. The study of relativistic magnetic reconnection in the magnetically…

High Energy Astrophysical Phenomena · Physics 2024-04-23 Fan Guo , Yi-Hsin Liu , Seiji Zenitani , Masahiro Hoshino

Relativistic jets are believed to be born magnetically dominated. Very and ultra-high energy cosmic rays can be efficiently accelerated by magnetic reconnection in these sources. We here demonstrate this directly, with no extrapolations to…

High Energy Astrophysical Phenomena · Physics 2022-04-21 E. De Gouveia Dal Pino , T. E. Medina-Torrejon , L. H. S. Kadowaki , G. Kowal , J. C. Rodriguez-Ramirez

A nonthermal particle acceleration mechanism involving the interaction of a charged particle with multiple magnetic islands is proposed. The original Fermi acceleration model, which assumes randomly distributed magnetic clouds moving at…

High Energy Astrophysical Phenomena · Physics 2012-04-03 Masahiro Hoshino

In space and astrophysical plasmas, like in planetary magnetospheres, as that of Mercury,energetic electrons are often found near current sheets (CSs), which hints at electron acceleration by magnetic reconnection. Unfortunately, electron…

Plasma Physics · Physics 2018-07-04 X. Zhou , J. Buechner , F. Widmer , P. A. Munoz

A new particle acceleration process in a developing Alfv\'{e}n turbulence in the course of successive parametric instabilities of a relativistic pair plasma is investigated by utilyzing one-dimensional electromagnetic full particle code.…

High Energy Astrophysical Phenomena · Physics 2014-11-20 S. Matsukiyo , T. Hada

This review aims at providing an up-to-date status and a general introduction to the subject of the numerical study of energetic particle acceleration and transport in turbulent astrophysical flows. The subject is also complemented by a…

High Energy Astrophysical Phenomena · Physics 2020-02-26 A. Marcowith , G. Ferrand , M. Grech , Z. Meliani , I. Plotnikov , R. Walder

Turbulence, magnetic reconnection, and shocks can be present in explosively unstable plasmas, forming a new electromagnetic environment, which we call here turbulent reconnection, and where spontaneous formation of current sheets takes…

High Energy Astrophysical Phenomena · Physics 2018-11-28 Loukas Vlahos , Heinz Isliker

We discuss the physics of stochastic particle acceleration in relativistic magnetohydrodynamic (MHD) turbulence, combining numerical simulations of test-particle acceleration in synthetic wave turbulence spectra with detailed analytical…

High Energy Astrophysical Phenomena · Physics 2020-07-06 Camilia Demidem , Martin Lemoine , Fabien Casse