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Related papers: Particle Acceleration at Relativistic Shocks

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Collisionless shock waves have long been considered amongst the most prolific particle accelerators in the universe. Shocks alter the plasma they propagate through and often exhibit complex evolution across multiple scales. Interplanetary…

We give a new coherent description of the first-order Fermi acceleration of particles in shock waves from the point of view of stochastic process of the individual particles, under the test particle approximation. The time development of…

Astrophysics · Physics 2009-11-07 Tsunehiko N. Kato , Fumio Takahara

Relativistic shocks accelerate particles by the first order Fermi mechanism. These particles then emit synchrotron emission in the post shock gas. We have developed a numerical code which integrates the relativistic Euler equations for…

Astrophysics · Physics 2009-11-06 T. P. Downes , P. Duffy , S. Komissarov

The shock waves produce relativistic particles via the diffusive shock acceleration (DSA) mechanism. Among various circumstances, fast acceleration has been expected for perpendicular shocks. We investigate the acceleration time and the…

High Energy Astrophysical Phenomena · Physics 2020-07-15 Shoma F. Kamijima , Yutaka Ohira , Ryo Yamazaki

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

The physics of collisionless relativistic shocks with a moderate magnetization is presented. Micro-physics is relevant to explain the most energetic radiative phenomena of Nature, namely that of the termination shock of Gamma Ray Bursts. A…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Guy Pelletier , Martin Lemoine , Laurent Gremillet , Illya Plotnikov

Shock acceleration is considered one of the most important mechanisms for the acceleration of astrophysical energetic particles. In this work, we calculate the trajectories of a large number of test charged particles accurately in a…

High Energy Astrophysical Phenomena · Physics 2019-04-17 F. -J. Kong , G. Qin , S. -S. Wu , L. -H. Zhang , H. -N. Wang , T. Chen , P. Sun

We investigate the acceleration of light particles in perpendicular shocks for plasmas consisting of a mixture of leptonic and hadronic particles. Starting from the full set of conservation equations for the mixed plasma constituents, we…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Stockem , F. Fiuza , R. A. Fonseca , L. O. Silva

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

An extreme case of electron shock drift acceleration in low Mach number collisionless shocks is investigated as a plausible mechanism of initial acceleration of relativistic electrons in large-scale shocks in galaxy clusters where upstream…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Shuichi Matsukiyo , Yutaka Ohira , Ryo Yamazaki , Takayuki Umeda

We study a type of particle acceleration that operates via neutron-proton conversion in inelastic nuclear collisions. This mechanism can be expected for relativistic shocks at subphotospheres if relativistic outflows contain neutrons. Using…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Kazumi Kashiyama , Kohta Murase , Peter Mészáros

Observations of both gamma-ray burst sources and certain classes of active galaxy indicate the presence of relativistic shock waves and require the production of high energy particles to explain their emission. In this paper we review the…

Astrophysics · Physics 2009-10-31 J. G. Kirk , P. Duffy

We perform numerical simulations of particle acceleration in relativistic, self-driven turbulent magnetic reconnection using the MHD-PIC method. We systematically investigate the dependence of the non-thermal particle spectral exponent on…

High Energy Astrophysical Phenomena · Physics 2026-04-30 Shi-Min Liang , Jian-Fu Zhang , Nian-Yu Yi

The question of the origin of ultra-high-energy cosmic rays at relativistic shock waves is discussed in the light of results of recent Monte Carlo studies of the first-order Fermi particle acceleration (Niemiec & Ostrowski 2006, Niemiec et…

Astrophysics · Physics 2007-05-31 Jacek Niemiec , Michal Ostrowski , Martin Pohl

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

Numerical Monte Carlo simulations of the diffusive shock acceleration in the test particle limit are investigated. We simulate high relativistic flow astrophysical plasmas for upstream $\gamma$ $\sim5$ and up to $\gamma$ $\sim1000$. These…

Astrophysics · Physics 2007-05-23 Athina Meli , John Quenby

One of the main features of astrophysical shocks is their ability to accelerate particles to extremely high energies. The leading acceleration mechanism, the diffusive shock acceleration is reviewed. It is demonstrated that its efficiency…

Astrophysics · Physics 2009-11-06 M. A. Malkov , P. H. Diamond

Particle acceleration in relativistic shocks is studied analytically in the test-particle, small-angle scattering limit, for an arbitrary velocity-angle diffusion function D. Accurate analytic expressions for the spectral index s are…

Astrophysics · Physics 2008-11-26 Uri Keshet

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

Different electron acceleration regimes in the evanescent field of a surface plasma wave are studied by considering the interaction of a test electron with the high-frequency electromagnetic field of a surface wave. The non-relativistic and…

Plasma Physics · Physics 2015-06-30 C. Riconda , M. Raynaud , T. Vialis , M. Grech
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