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Related papers: Shock acceleration in partially neutral plasmas

200 papers

The excitation of nonlinear electrostatic waves, such as shock and solitons, by ultraintense laser interaction with overdense plasmas and related ion acceleration are investigated by numerical simulations. Stability of solitons and…

Plasma Physics · Physics 2015-06-03 Andrea Macchi , Amritpal Singh Nindrayog , Francesco Pegoraro

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

We develop a self-consistent nonlinear extension of diffusive shock acceleration that incorporates cosmic ray (CR) backreaction on the shock precursor together with a physically motivated upstream-escape mechanism that produces an…

High Energy Astrophysical Phenomena · Physics 2026-02-17 Han-Xiang Hu , Xing-Jian Lv , Xiao-Jun Bi , Tian-Lu Chen , Kun Fang , Peng-Fei Yin

According to the most popular model for the origin of cosmic rays (CRs), supernova remnants (SNRs) are the site where CRs are accelerated. Observations across the electromagnetic spectrum support this picture through the detection of…

High Energy Astrophysical Phenomena · Physics 2021-01-27 S. Orlando , M. Miceli , S. Ustamujic , A. Tutone , E. Greco , O. Petruk , F. Bocchino , G. Peres

While collisionless plasmas are ubiquitously present near astrophysical compact objects, the impact that their composition has on the high-energy emission is presently unknown. We present the first investigation of particle-acceleration…

High Energy Astrophysical Phenomena · Physics 2026-04-09 Claudio Meringolo , Mario Imbrogno , Alejandro Cruz-Osorio , Sergio Servidio , Luciano Rezzolla

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…

Theoretical concepts ofn cosmic ray particle acceleration at relativistic plasma flows -- shocks and shear layers -- are reviewed. We begin with a discussion of mildly relativistic shock waves. The role of oblique field configurations and…

Astrophysics · Physics 2007-05-23 M. Ostrowski

We have modeled the simultaneous first-order Fermi shock acceleration of protons, electrons, and helium nuclei by relativistic shocks. By parameterizing the particle diffusion, our steady-state Monte Carlo simulation allows us to follow…

High Energy Astrophysical Phenomena · Physics 2015-07-15 Donald C. Warren , Donald C. Ellison , Andrei M. Bykov , Shiu-Hang Lee

Recent precise measurements of cosmic ray (CR) spectra show that the energy distribution of protons is softer than those of heavier nuclei, and there are spectral hardenings for all nuclear compositions above $\sim$200 GV. Models proposed…

High Energy Astrophysical Phenomena · Physics 2017-08-02 Yiran Zhang , Siming Liu , Qiang Yuan

Synchrotron X-ray emission in young supernova remnants (SNRs) is a powerful diagnostic tool to study the population of high energy electrons accelerated at the shock front and the acceleration process. We performed a spatially resolved…

Radiative shocks, behind which gas cools faster than the dynamical time, play a key role in many astrophysical transients, including classical novae and young supernovae interacting with circumstellar material. The dense layer behind high…

High Energy Astrophysical Phenomena · Physics 2018-07-04 Elad Steinberg , Brian D. Metzger

We present a survey of 1D kinetic particle-in-cell simulations of quasi-parallel non-relativistic shocks to identify the environments favorable for electron acceleration. We explore an unprecedented range of shock speeds $v_{\rm sh}\approx…

High Energy Astrophysical Phenomena · Physics 2024-08-30 Siddhartha Gupta , Damiano Caprioli , Anatoly Spitkovsky

Collisionless shocks with low sonic Mach numbers, $M_{\rm s} \lesssim 4$, are expected to accelerate cosmic ray (CR) protons via diffusive shock acceleration (DSA) in the intracluster medium (ICM). However, observational evidence for CR…

High Energy Astrophysical Phenomena · Physics 2018-10-10 Ji-Hoon Ha , Dongsu Ryu , Hyesung Kang , Allard Jan van Marle

The supernova remnant (SNR) RCW86 is among the few SNRs with Balmer-emission lines containing broad and narrow spectral components that trace fast, non-radiative shocks in partially-ionized gas.\ These are invaluable laboratories for…

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

Collisionless relativistic shocks have been the focus of intense theoretical and numerical investigations in recent years. The acceleration of particles, the generation of electromagnetic microturbulence and the building up of a shock front…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Illya Plotnikov , Guy Pelletier , Martin Lemoine

During the formation of large-scale structures in the universe, weak internal shocks are induced within the hot ICM, while strong accretion shocks arise in the WHIM within filaments, and the warm-cold gas in voids surrounding galaxy…

High Energy Astrophysical Phenomena · Physics 2024-09-30 Hyesung Kang

A leading explanation for the origin of Galactic cosmic rays is acceleration at high-Mach number shock waves in the collisionless plasma surrounding young supernova remnants. Evidence for this is provided by multi-wavelength non-thermal…

High Energy Astrophysical Phenomena · Physics 2017-08-02 A. Masters , A. H. Sulaiman , Ł. Stawarz , B. Reville , N. Sergis , M. Fujimoto , D. Burgess , A. J. Coates , M. K. Dougherty

Galactic cosmic rays are widely believed to be accelerated in expanding shock waves initiated by supernova explosions. The theory of diffusive shock acceleration of cosmic rays is now well established, but two fundamental questions remain…

Astrophysics · Physics 2008-07-25 Vincent Tatischeff

lasma instabilities excited in collisionless shocks are responsible for particle acceleration. We have investigated the particle acceleration and shock structure associated with an unmagnetized relativistic electron-positron jet propagating…

High Energy Astrophysical Phenomena · Physics 2015-06-03 K. -I. Nishikawa , E. J. Choi , K. Min , P. Hardee , Y. Mizuno , B. Zhang , J. Niemiec , M. Medvedev , A. Nordlund , J. Fredriksen , M. Pohl , H. Sol , D. H. Hartmann , G. J. Fishman