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Related papers: In-situ Particle Acceleration in Collisionless Sho…

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We present a new, semi-analytic formalism to model the acceleration and collimation of relativistic jets in a gravitational potential. The gravitational energy density includes the kinetic, thermal, and electromagnetic mass contributions.…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Peter Polko , David L. Meier , Sera Markoff

Relativistic magnetized jets from active galaxies are among the most powerful cosmic accelerators, but their particle acceleration mechanisms remain a mystery. We present a new acceleration mechanism associated with the development of the…

High Energy Astrophysical Phenomena · Physics 2018-12-19 E. Paulo Alves , Jonathan Zrake , Frederico Fiuza

There is no single mechanism by which fast particles are accelerated in astrophysical environments, and it is now recognized that the data require a rich variety of different mechanisms operating under different conditions. The mechanisms…

High Energy Astrophysical Phenomena · Physics 2011-07-15 Elisabete M. de Gouveia Dal Pino , Grzegorz Kowal , Alex Lazarian , Reinaldo Santos-Lima

Diffusive shock acceleration at collisionless shocks is thought to be the source of many of the energetic particles observed in space. Large-scale spatial variations of the magnetic field has been shown to be important in understanding…

High Energy Astrophysical Phenomena · Physics 2015-05-20 F. Guo , J. R. Jokipii , J. Kota

The theory of particle acceleration at shock fronts is briefly reviewed, with special emphasis on the production of the particles responsible for the nonthermal emission from blazars. The flat radio/IR spectra of these sources cannot be…

Astrophysics · Physics 2007-05-23 J. G. Kirk

Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities) created in collisionless shocks are responsible for particle…

Astrophysics · Physics 2009-11-10 K. -I. Nishikawa , P. Hardee , G. Richardson , R. Preece , H. Sol , G. J. Fishman

Electron accelerations at high Mach number collision-less shocks are investigated by means of two-dimensional electromagnetic Particle-in-Cell simulations with various Alfven Mach numbers, ion-to-electron mass ratios, and the upstream…

High Energy Astrophysical Phenomena · Physics 2013-11-01 Yosuke Matsumoto , Takanobu Amano , Masahiro Hoshino

Relativistic particle acceleration in collisionless shocks of supernova remnants is accompanied by magnetic field amplification from cosmic ray (CR) driven plasma instabilities. Bell's fast CR-current instability is predicted to produce…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Sergei M Osipov , Andrei M Bykov , Donald C Ellison

We use large hybrid (kinetic protons-fluid electrons) simulations to investigate the transport of energetic particles in self-consistent electromagnetic configurations of collisionless shocks. In previous papers of this series, we showed…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Damiano Caprioli , Anatoly Spitkovsky

We present the first laboratory observations of time-resolved electron and ion velocity distributions in forming, magnetized collisionless shocks. Thomson scattering of a probe laser beam was used to observe the interaction of a…

Observations suggest that relativistic particles play a fundamental role in the dynamics of jets emerging from active galactic nuclei as well as in their interaction with the intracluster medium. However, no general consensus exists…

High Energy Astrophysical Phenomena · Physics 2015-06-11 J. A. de Freitas Pacheco , J. Gariel , G. Marcilhacy , N. O. Santos

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

In this work we used Particle-In-Cell simulations to study the interaction of circularly polarised Alfv\'en waves with one dimensional plasma density inhomogeneities transverse to the uniform magnetic field (phase mixing) in collisionless…

Astrophysics · Physics 2007-05-23 David Tsiklauri , Jun-Ichi Sakai , Shinji Saito

We analyse processes of particle acceleration in the Fermi Bubbles. The goal of our investigations is to obtain restrictions for acceleration mechanisms. Our analysis of the three processes: acceleration from background plasma,…

High Energy Astrophysical Phenomena · Physics 2015-06-18 V. A. Dogiel , K. -S. Cheng , D. O. Chernyshov , C. -M. Ko

We simulate the acceleration processes of collisionless particles in a shock structure with magnetohydrodynamical (MHD) fluctuations. The electromagnetic field is represented as a sum of MHD shock solution ($\Mag_0, \Ele_0$) and torsional…

Astrophysics · Physics 2009-11-13 Takayuki Muranushi , Shu-ichiro Inutsuka

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 acceleration of ultra high energy cosmic rays is conjectured to occur through various interactions with the electromagnetic fields in different astrophysical objects, like magnetic matter clumps, besides the well-known shock and…

High Energy Astrophysical Phenomena · Physics 2014-03-18 A. Tawfik , A. Saleh , M. T. Ghoneim , A. A. Hady

First order Fermi acceleration at astrophysical shocks is often invoked as a mechanism for the generation of non-thermal particles. This mechanism is especially simple in the approximation that the accelerated particles behave like test…

Astrophysics · Physics 2015-06-24 Pasquale Blasi

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…

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
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