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Related papers: Non-thermal Acceleration from Reconnection Shocks

200 papers

We investigate shock structure and particle acceleration in relativistic magnetized collisionless electron-ion shocks by means of 2.5D particle-in-cell simulations with ion-to-electron mass ratios (m_i/m_e) ranging from 16 to 1000. We…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Lorenzo Sironi , Anatoly Spitkovsky

In magnetized astrophysical outflows, the dissipation of field energy into particle energy via magnetic reconnection is often invoked to explain the observed non-thermal signatures. By means of two- and three-dimensional particle-in-cell…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Lorenzo Sironi , Anatoly Spitkovsky

Collisionless shocks tend to send charged particles into the upstream, driving electric currents through the plasma. Using kinetic particle-in-cell simulations, we investigate how the background thermal plasma neutralizes such currents in…

High Energy Astrophysical Phenomena · Physics 2023-12-22 Siddhartha Gupta , Damiano Caprioli , Anatoly Spitkovsky

We perform particle-in-cell simulations of perpendicular nonrelativistic collisionless shocks to study electron heating and pre-acceleration for parameters that permit extrapolation to the conditions at young supernova remnants. Our…

High Energy Astrophysical Phenomena · Physics 2017-10-04 Artem Bohdan , Jacek Niemiec , Oleh Kobzar , Martin Pohl

In this review we discuss some observational aspects and theoretical models of astrophysical collisionless shocks in partly ionized plasma with the presence of non-thermal components. A specific feature of fast strong collisionless shocks…

High Energy Astrophysical Phenomena · Physics 2015-06-15 A. M. Bykov , M. A. Malkov , J. C. Raymond , A. M. Krassilchtchikov , A. E. Vladimirov

Shock waves propagating in collisionless heliospheric and astrophysical plasmas have been studied extensively over the decades. One prime motivation is to understand the nonthermal particle acceleration at shocks. Although the theory of…

High Energy Astrophysical Phenomena · Physics 2022-09-09 T. Amano , Y. Matsumoto , A. Bohdan , O. Kobzar , S. Matsukiyo , M. Oka , J. Niemiec , M. Pohl , M. Hoshino

We propose that non-thermal electrons are efficiently accelerated by first-order Fermi process at the fast shock, as a natural consequence of the new magnetohydrodynamic picture of the flaring region revealed with Yohkoh. An oblique fast…

Astrophysics · Physics 2009-10-30 Saku Tsuneta , Tsuguya Naito

Multi-dimensional particle-in-cell simulations are used to study the generation of electrostatic shocks in plasma and the reflection of background ions to produce high-quality and high-energy ion beams. Electrostatic shocks are driven by…

Strong non-relativistic shocks are known to accelerate particles up to relativistic energies. However, for Diffusive Shock Acceleration electrons must have a highly suprathermal energy, implying a need for very efficient pre-acceleration.…

Plasma Physics · Physics 2023-10-24 Karol Fulat , Artem Bohdan , Gabriel Torralba Paz , Martin Pohl

The course of non-thermal electron ejection in relativistic unmagnetized electron-ion shocks is investigated by performing self-consistent particle-in-cell simulations. The shocks are excited through the injection of relativistic jet into…

High Energy Astrophysical Phenomena · Physics 2016-08-24 Kazem Ardaneh , Dongsheng Cai , Ken-Ichi Nishikawa

Magnetic reconnection and turbulence in magnetically-dominated environments have been proposed as important nonthermal particle acceleration mechanisms that generate high energy particles and associated emissions. While the acceleration to…

Plasma Physics · Physics 2025-06-26 Fan Guo , Omar French , Qile Zhang , Xiaocan Li , Jeongbhin Seo

Ab-initio numerical study of collisionless shocks in electron-ion unmagnetized plasmas is performed with fully relativistic particle in cell simulations. The main properties of the shock are shown, focusing on the implications for particle…

High Energy Astrophysical Phenomena · Physics 2011-02-11 S. F. Martins , R. A. Fonseca , L. O. Silva , W. B. Mori

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

Electron acceleration to non-thermal energies in low Mach number (M<5) shocks is revealed by radio and X-ray observations of galaxy clusters and solar flares, but the electron acceleration mechanism remains poorly understood. Diffusive…

High Energy Astrophysical Phenomena · Physics 2014-10-14 Xinyi Guo , Lorenzo Sironi , Ramesh Narayan

We study the thermalization, injection, and acceleration of ions with different mass/charge ratios, $A/Z$, in non-relativistic collisionless shocks via hybrid (kinetic ions-fluid electrons) simulations. In general, ions thermalize to a…

High Energy Astrophysical Phenomena · Physics 2017-11-01 Damiano Caprioli , Dennis T. Yi , Anatoly Spitkovsky

The expansion of a dense plasma through a more rarefied ionised medium is a phenomenon of interest in various physics environments ranging from astrophysics to high energy density laser- matter laboratory experiments. Here this situation is…

Plasma Physics · Physics 2015-05-19 G. Sarri , I. Kourakis , M. E. Dieckmann , M. Borghesi

We investigate the interaction of nonthermal ions (protons and nuclei) accelerated in an ultrarelativistic blastwave with the pre-existing magnetic field of the medium into which the blastwave propagates. While particle acceleration…

Astrophysics · Physics 2009-11-13 Sean M. Couch , Milos Milosavljevic , Ehud Nakar

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

A review of the main issues in the field of particle acceleration in Supernova Remnants is provided in the context of future X-ray observations with Simbol-X. After a summary of the nonthermal acceleration mechanisms at work, I briefly…

Astrophysics · Physics 2008-02-05 Anne Decourchelle

Magnetic Reconnection is an efficient and fast acceleration mechanism by means of direct electric field acceleration parallel to the magnetic field. Thus, acceleration of particles in reconnection regions is a very important topic in plasma…

Astrophysics · Physics 2015-06-24 Rudiger Schopper , Guido T. Birk , Harald Lesch