English
Related papers

Related papers: Super-Fermi Acceleration in Multiscale MHD Reconne…

200 papers

We investigate electron acceleration resulting from 3D magnetic reconnection between an emerging, twisted magnetic flux rope and a pre-existing weak, open magnetic field. We first follow the rise of an unstable, twisted flux tube with a…

Solar and Stellar Astrophysics · Physics 2012-11-07 G. Baumann , Å. Nordlund

The mechanism that accelerates particles to the energies required to produce the observed high-energy impulsive emission in solar flares is not well understood. Drake et al. (2006) proposed a mechanism for accelerating electrons in…

Solar and Stellar Astrophysics · Physics 2016-03-23 S. E. Guidoni , C. R. DeVore , J. T. Karpen , B. J. Lynch

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

Magnetic reconnection in relativistic plasmas -- where the magnetization $\sigma\gg1$ -- is regarded as an efficient particle accelerator, capable of explaining the most dramatic astrophysical flares. We employ two-dimensional (2D)…

High Energy Astrophysical Phenomena · Physics 2025-01-03 Sanya Gupta , Navin Sridhar , Lorenzo Sironi

The first self-consistent simulations of electron acceleration during magnetic reconnection in a macroscale system are presented. Consistent with solar flare observations the spectra of energetic electrons take the form of power-laws that…

We investigate the physics of particle acceleration at non-relativistic shocks exploiting two different and complementary approaches, namely a semi-analytic modeling of cosmic-ray modified shocks and large hybrid (kinetic protons/fluid…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Damiano Caprioli

Electron and proton acceleration in three-dimensional electric and magnetic fields is studied through test particle simulations. The fields are obtained by a three-dimensional magnetohydrodynamic simulation of magnetic reconnection in slab…

Astrophysics · Physics 2008-11-26 Marco Onofri , Heinz Isliker , Loukas Vlahos

The effects of a finite guide field on the distribution of plasmoids in high-Lundquist-number current sheets undergoing magnetic reconnection in large plasmas are investigated with statistical models. Merging of plasmoids is taken into…

Plasma Physics · Physics 2021-09-10 Stephen Majeski , Hantao Ji , Jonathan Jara-Almonte , Jongsoo Yoo

Magnetic reconnection is a primary driver of particle acceleration processes in space and astrophysical plasmas. Understanding how particles are accelerated and the resulting particle energy spectra is among the central topics in…

Plasma Physics · Physics 2021-06-16 Xiaocan Li , Fan Guo , Yi-Hsin Liu

A set of reduced Hall magnetohydrodynamic (MHD) equations are used to evaluate the stability of large aspect ratio current sheets to the formation of plasmoids (secondary islands). Reconnection is driven by resistivity in this analysis,…

Plasma Physics · Physics 2015-05-30 S. D. Baalrud , A. Bhattacharjee , Y. -M. Huang , K. Germaschewski

The Fermi acceleration model was introduced to describe how cosmic ray particles are accelerated to great speeds by interacting with moving magnetic fields. We identify a new variation of the model where light ions interact with a moving…

Plasma Physics · Physics 2022-02-02 J. C. Waybright , M. E. Mlodik , N. J. Fisch

The plasmoid-induced-reconnection model explaining solar flares based on bursty reconnection produced by an ejecting plasmoid suggests a possible relation between the ejection velocity of a plasmoid and the rate of magnetic reconnection. In…

Fermi acceleration can take place at ultra-relativistic shock waves if the upstream or downstream magnetic field has been remodeled so that most of the magnetic power lies on short spatial scales. The relevant conditions under which Fermi…

Astrophysics · Physics 2009-11-13 Guy Pelletier , Martin Lemoine , Alexandre Marcowith

By means of fully kinetic simulations, we investigate electron acceleration during magnetic reconnection in a nonrelativistic proton--electron plasma with conditions similar to solar corona and flares. We demonstrate that reconnection leads…

Solar and Stellar Astrophysics · Physics 2015-09-29 Xiaocan Li , Fan Guo , Hui Li , Gang Li

Magnetic reconnection is a ubiquitous process in astrophysical plasmas and an efficient mechanism for particle acceleration. Using 2.5D magnetohydrodynamic (MHD) simulations with a co-evolving fluid-particle framework, we investigate how…

Plasma Physics · Physics 2026-01-01 Shimin Liang , Nianyu Yi

The excitation of surface plasmons with ultra-intense ($I\sim 5\times 10^{19}$ W/cm$^2$), high contrast ($\sim 10^{12}$) laser pulses on periodically-modulated solid targets has been recently demonstrated to produce collimated bunches of…

We calculate the momentum distribution of the Fermi liquid phase of the homogeneous, two-dimensional electron gas. We show that, close to the Fermi surface, the momentum distribution of a finite system with $N$ electrons approaches its…

Strongly Correlated Electrons · Physics 2011-05-13 Markus Holzmann , Bernard Bernu , Valerio Olevano , Richard M. Martin , David M. Ceperley

Collisionless, magnetized turbulence offers a promising framework for the generation of non-thermal high-energy particles in various astrophysical sites. Yet, the detailed mechanism that governs particle acceleration has remained subject to…

High Energy Astrophysical Phenomena · Physics 2022-08-17 Virginia Bresci , Martin Lemoine , Laurent Gremillet , Luca Comisso , Lorenzo Sironi , Camilia Demidem

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

We analyze particle acceleration in explosive reconnection events in magnetically dominated proton-electron plasmas. Reconnection is driven by large-scale magnetic stresses in interacting current-carrying flux tubes. Our model relies on…

High Energy Astrophysical Phenomena · Physics 2019-02-07 B. Ripperda , O. Porth , C. Xia , R. Keppens