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Related papers: Pre-acceleration in the Electron Foreshock I: Elec…

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The rate at which particles are accelerated by the first-order Fermi mechanism in shocks depends on the angle, \teq{\Tbone}, that the upstream magnetic field makes with the shock normal. The greater the obliquity the greater the rate, and…

Astrophysics · Physics 2009-10-28 D. C. Ellison , M. G. Baring , F. C. Jones

Solar wind ion reflection at collisionless shocks regulates foreshock plasma dynamics, yet the quantitative dependence of reflected ion properties on upstream and shock-related parameters remains unclear, causing difficulties in predicting…

Space Physics · Physics 2026-03-30 Runyi Liu , Terry Liu , Kun Zhang , Vassilis Angelopoulos , Siqi Zhao

Relativistic shocks propagating into a medium with low magnetization are generated and sustained by small-scale but very strong magnetic field turbulence. This so-called "microturbulence" modifies the typical shock acceleration process, and…

High Energy Astrophysical Phenomena · Physics 2024-08-16 Donald C. Warren , Catherine A. A. Beauchemin , Maxim V. Barkov , Shigehiro Nagataki

We calculate the energy spectra of cosmic ray (CR) protons and electrons at a plane shock with quasi-parallel magnetic fields, using time-dependent, diffusive shock acceleration (DSA) simulations, including energy losses via synchrotron…

High Energy Astrophysical Phenomena · Physics 2017-01-18 Hyesung Kang

We discuss that energetic electrons are generated near the X-type magnetic reconnection region due to a surfing acceleration mechanism. In a thin plasma sheet, the polarization electric fields pointing towards the neutral sheet are induced…

Astrophysics · Physics 2015-06-24 Masahiro Hoshino

Using plasma mirror injection we demonstrate, both analytically and numerically, that a circularly polarized helical laser pulse can accelerate highly collimated dense bunches of electrons to several hundred MeV using currently available…

Plasma Physics · Physics 2023-06-14 Yin Shi , David Blackman , Alexey Arefiev

Many particles are accelerated during solar flares. To understand the acceleration and propagation processes of electrons, we require the pitch-angle distributions of the particles. The pitch angle of accelerated electrons has been…

Solar and Stellar Astrophysics · Physics 2023-10-06 Keitarou Matsumoto , Satoshi Masuda , Takafumi Kaneko

We extend the eigenfunction method of computing the power-law spectrum of particles accelerated at a relativistic shock fronts to apply to shocks of arbitrarily high Lorentz factor. In agreement with the findings of Monte-Carlo simulations,…

Astrophysics · Physics 2009-10-31 J. G. Kirk , A. W. Guthmann , Y. A. Gallant , A. Achterberg

A major attraction of diffusive shock acceleration is the prediction of power-law spectra for energetic particle distributions. However, this property is not fundamental to the theory. We demonstrate that for planar shocks with an oblique…

High Energy Astrophysical Phenomena · Physics 2025-11-04 Asma Shirin T , Brian Reville , Nils W. Schween , Florian Schulze , John G. Kirk

The process of cosmic ray first-order Fermi acceleration at relativistic shock waves is studied with the method of Monte Carlo simulations. The simulations are based on numerical integration of particle equations of motion in a turbulent…

Astrophysics · Physics 2009-11-10 Jacek Niemiec , Michal Ostrowski

We calculate the electron acceleration in random superluminal strong waves (SLSWs) and radiation from them by using numerical methods in the context of the termination shock of the pulsar wind nebulae. We pursue the electrons by solving the…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Yuto Teraki , Hirotaka Ito , Shigehiro Nagataki

A study of collisionless external shocks in gamma-ray bursts is presented. The shock structure, electromagnetic fields, and process of electron acceleration are assessed by performing a self-consistent 3D particle-in-cell (PIC) simulation.…

High Energy Astrophysical Phenomena · Physics 2015-09-30 Kazem Ardaneh , Dongsheng Cai , Ken-Ichi Nishikawa , Bertrand Lembége

We use kinetic hybrid simulations (kinetic ions - fluid electrons) to characterize the fraction of ions that are accelerated to non-thermal energies at non-relativistic collisionless shocks. We investigate the properties of the shock…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Damiano Caprioli , Ana-Roxana Pop , Anatoly Spitkovsky

A possibility of electrodynamic acceleration of particles from the initial zero velocity to the final velocity ten kilometeres per second the acceleration length five meters is considered. After the electrostatic preacceleration particles…

Accelerator Physics · Physics 2013-11-22 S. N. Dolya

Molecular dynamics simulations are used to study the mechanism and kinetics of hydrated electron diffusion. The electron center of mass is found to exhibit Brownian-type behavior with a diffusion coefficient considerably greater than that…

Chemical Physics · Physics 2012-11-06 Kafui A. Tay , François-Xavier Coudert , Anne Boutin

A high-intensity laser beam propagating through a dense plasma drives a strong current that robustly sustains a strong quasi-static Mega Tesla-level azimuthal magnetic field. The transverse laser field efficiently accelerates electrons in…

Plasma Physics · Physics 2020-07-22 Z. Gong , F. Mackenroth , T. Wang , X. Q. Yan , T. Toncian , A. V. Arefiev

In the theory of diffusive acceleration at oblique shock fronts the question of the existence of a discontinuity of energetic particle density is contentious. The resolution of this problem is interesting from a theoretical point of view,…

Astrophysics · Physics 2011-05-23 U. D. J. Gieseler , J. G. Kirk , Y. A. Gallant , A. Achterberg

The grid of the models of radiative shock waves propagating through partially ionized hydrogen gas with temperature 3000K <= T_1 <= 8000K and density 10^{-12} gm/cm^3 <= \rho_1 <= 10^{-9}gm/cm^3 is computed for shock velocities 20 km/s <=…

Astrophysics · Physics 2009-11-06 Yu. A. Fadeyev , D. Gillet

Particle acceleration at magnetized purely perpendicular relativistic shocks in electron-ion plasmas are studied by means of two-dimensional particle-in-cell simulations. Magnetized shocks with the upstream bulk Lorentz factor $\gamma_1 \gg…

High Energy Astrophysical Phenomena · Physics 2022-01-20 Masanori Iwamoto , Takanobu Amano , Yosuke Matsumoto , Shuichi Matsukiyo , Masahiro Hoshino

We consider the acceleration of charged particles near ultra-relativistic shocks, with Lorentz factor Gamma_s >> 1. We present simulations of the acceleration process and compare these with results from semi-analytical calculations. We show…

Astrophysics · Physics 2014-10-13 Abraham Achterberg , Yves A. Gallant , John G. Kirk , Axel W. Guthmann