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

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We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given…

Astrophysics · Physics 2008-11-26 Frank M. Rieger , Valenti Bosch-Ramon , Peter Duffy

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

The generic acceleration model for ultra high energy cosmic rays, which has been introduced in {\tt 1006.5708 [astro-ph.HE]}, suggests various types of electromagnetic interactions between cosmic charged particles and the different types of…

High Energy Astrophysical Phenomena · Physics 2014-03-18 A. Tawfik , A. Saleh

Magnetic reconnection and non-thermal particle distributions associated with current-driven instabilities are investigated by means of resistive magnetohydrodynamics (MHD) simulations combined with relativistic test particle methods. We…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Bart Ripperda , Oliver Porth , Chun Xia , Rony Keppens

Collisionless plasma shock theory, which applies for example to the afterglow of gamma ray bursts, still contains key issues that are poorly understood. In this paper we study charged particle dynamics in a highly relativistic collisionless…

Astrophysics · Physics 2009-11-10 C. B. Hededal , T. Haugboelle , J. Trier Frederiksen , Å. Nordlund

Processes driven by unsteady reconnection can efficiently accelerate particles in many astrophysical plasmas. An example are the reconnection jet fronts in an outflow region. We present evidence of suprathermal ion acceleration between two…

We develop a theory of particle acceleration inside relativistic rotating electron-positron force-free jets with spiral magnetic fields. We considered perturbation of the stationary magnetic field structure and found that acceleration takes…

Astrophysics · Physics 2009-11-07 A. R. Beresnyak , Ya. N. Istomin , V. I. Pariev

Mathematics demonstrates that an ideally evolving magnetic field has an exponentially increasing sensitivity to non-ideal effects for all but truly exceptional evolutions. On a time scale that depends only logarithmically on the magnitude…

Plasma Physics · Physics 2020-01-29 Allen H. Boozer

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

Centrifugal acceleration of charged test particles at the base of a rotating jet magnetosphere is considered. Based on an analysis of forces we derive the equation for the radial accelerated motion and present an analytical solution. It is…

Astrophysics · Physics 2009-10-31 F. M. Rieger , K. Mannheim

Magnetic reconnection in strongly magnetized astrophysical plasma environments is believed to be the primary process for fast energy release and particle energization. Currently there is strong interest in relativistic magnetic…

High Energy Astrophysical Phenomena · Physics 2020-08-26 Fan Guo , Yi-Hsin Liu , Xiaocan Li , Hui Li , William Daughton , Patrick Kilian

We study linear and nonlinear development of relativistic and ultrarelativistic current sheets of pair plasmas with antiparallel magnetic fields. Two types of two-dimensional problems are investigated by particle-in-cell simulations. First,…

Astrophysics · Physics 2011-11-10 S. Zenitani , M. Hoshino

Blobs, or quasi-spherical emission regions containing relativistic particles and magnetic fields, are often assumed ad hoc in emission models of relativistic astrophysical jets, yet their physical origin is still not well understood. Here,…

High Energy Astrophysical Phenomena · Physics 2016-08-17 L. Sironi , D. Giannios , M. Petropoulou

We investigate the distribution of particle acceleration sites, independently of the actual acceleration mechanism, during plasmoid-dominated, relativistic collisionless magnetic reconnection by analyzing the results of a particle-in-cell…

High Energy Astrophysical Phenomena · Physics 2015-12-23 Krzysztof Nalewajko , Dmitri A. Uzdensky , Benoît Cerutti , Gregory R. Werner , Mitchell C. Begelman

Magnetic reconnection in strongly magnetized (low-beta), weakly collisional plasmas is investigated using a novel fluid-kinetic model [Zocco & Schekochihin, Phys. Plasmas 18, 102309 (2011)] which retains non-isothermal electron kinetics. It…

Plasma Physics · Physics 2015-06-12 N. F. Loureiro , A. A. Schekochihin , A. Zocco

In this chapter, we review some features of particle acceleration in astrophysical jets. We begin by describing four observational results relating to the topic, with particular emphasis on jets in active galactic nuclei and parallels…

High Energy Astrophysical Phenomena · Physics 2020-11-11 James Matthews , Anthony Bell , Katherine Blundell

Fermi acceleration is believed as a crucial process for the acceleration of energetic electrons within flux ropes (FRs) during magnetic reconnection. However, in finite-length FRs with a large core field, the finite contracting and the…

Space Physics · Physics 2025-06-12 Z. H. Zhong , H. Zhang , M. Zhou , D. B. Graham , R. X. Tang , X. H. Deng , Yu. V. Khotyaintsev

Plasmoid instability is usually accounted for the onset of fast reconnection events observed in astrophysical plasmas. However, the measured reconnection rate from observations can be one order of magnitude higher than that derived from MHD…

Solar and Stellar Astrophysics · Physics 2024-07-03 Abdullah Zafar , Lei Ni , Jun Lin , Ahmad Ali

Rapid and luminous flares of non-thermal radiation observed in blazars require an efficient mechanism of energy dissipation and particle acceleration in relativistic active galactic nuclei (AGN) jets. Particle acceleration in relativistic…

High Energy Astrophysical Phenomena · Physics 2016-09-08 Krzysztof Nalewajko

We present simulations of magnetized astrophysical shocks taking into account the interplay between the thermal plasma of the shock and supra-thermal particles. Such interaction is depicted by combining a grid-based magneto-hydrodynamics…

High Energy Astrophysical Phenomena · Physics 2017-10-02 Allard Jan van Marle , Fabien Casse , Alexandre Marcowith
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