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Related papers: Whence particle acceleration

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Motivated by the detection of very high energy gamma-rays deep in the afterglow emission of a gamma-ray burst, we revisit predictions of the maximum energy to which electrons can be accelerated at a relativistic blast wave. Acceleration at…

High Energy Astrophysical Phenomena · Physics 2022-02-09 Zhi-Qiu Huang , John Kirk , Gwenael Giacinti , Brian Reville

A mechanism of ultra-high energy cosmic ray acceleration in extragalactic radio sources, at the interface between the relativistic jet and the surrounding medium, is discussed as a supplement to the shock acceleration in `hot spots'. Due to…

Astrophysics · Physics 2007-05-23 M. Ostrowski

Gamma-ray bursts are often the brightest objects in the sky during their short life. Particle acceleration in trans-relativistic shocks, internal to the main blastwave, may explain the early intensity peaks, and particle acceleration in the…

Astrophysics · Physics 2007-05-23 Glen Paul Double

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

We study diffusive shock acceleration (DSA) of protons and electrons at nonrelativistic, high Mach number, quasiparallel, collisionless shocks by means of self-consistent 1D particle-in-cell simulations. For the first time, both species are…

High Energy Astrophysical Phenomena · Physics 2015-03-02 Jaehong Park , Damiano Caprioli , Anatoly Spitkovsky

Particle acceleration in relativistic shocks is not a very well understood subject. Owing to that difficulty, radiation spectra from relativistic shocks, such as those in GRB afterglows, have been often modelled by making assumptions about…

Astrophysics · Physics 2009-11-13 L. Resmi , D. Bhattacharya

We derive a relativistically covariant (although not manifestly so) equation for the distribution function of particles accelerated at shocks, which applies also to extremely relativistic shocks, and arbitrarily anisotropic particle…

Astrophysics · Physics 2009-11-07 Mario Vietri

Electron acceleration in high Mach number perpendicular shocks is investigated through two-dimensional electrostatic particle-in-cell (PIC) simulation. We simulate the shock foot region by modeling particles that consist of three components…

Astrophysics · Physics 2009-11-13 Yutaka Ohira , Fumio Takahara

Seventy crossings of the Earths bow shock by the THEMIS satellites have been used to study thermal electron heating in collisionless, quasi-perpendicular shocks. It was found that the temperature increase of thermal electrons differed from…

Plasma Physics · Physics 2013-02-11 F. S. Mozer , David Sundkvist

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

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

The theory of first order Fermi acceleration at shocks assumes that particles diffuse due to scattering off slow-moving magnetic irregularities. However, cosmic rays are closely tied to magnetic field lines, and the transport process,…

Astrophysics · Physics 2011-05-23 P. Duffy , J. G. Kirk , Y. A. Gallant , R. O. Dendy

Laboratory experiments to explore plasma conditions and stimulated particle acceleration can illuminate aspects of the cosmic particle acceleration process. Here we discuss the cosmic-ray candidate source object variety, and what has been…

High Energy Astrophysical Phenomena · Physics 2009-12-15 Roland Diehl

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

Particle acceleration at astrophysical shocks may be very efficient if magnetic scattering is self-generated by the same particles. This nonlinear process adds to the nonlinear modification of the shock due to the dynamical reaction of the…

Astrophysics · Physics 2009-11-11 Elena Amato , Pasquale Blasi

Using our new 3-D relativistic electromagnetic particle (REMP) code parallelized with MPI, we investigated long-term particle acceleration associated with a relativistic electron-positron jet propagating in an unmagnetized ambient…

High Energy Astrophysical Phenomena · Physics 2014-11-20 K. -I. Nishikawa , J. Niemiec , M. Medvedev , B. Zhang , P. Hardee , Y. Mizuno , A. Nordlund , J. Frederiksen , H. Sol , M. Pohl , D. H. Hartmann , J. F. Fishman

Short timescale variability is often associated with a black hole system. The consequence of an electromagnetic outflow suddenly generated near a Kerr black hole is considered assuming that it is described by a solution of a force-free…

General Relativity and Quantum Cosmology · Physics 2020-12-25 Yasufumi Kojima , Yuto Kimura

New particle acceleration schemes open up exciting opportunities, potentially providing more compact or higher-energy accelerators. The AWAKE experiment at CERN is currently taking data to establish the method of proton-driven plasma…

Accelerator Physics · Physics 2019-09-04 M. Wing

Several types of foreshock transients upstream of Earth's bow shock possessing a tenuous, hot core have been observed and simulated. Because of the low dynamic pressure in their cores, these phenomena can significantly disturb the bow shock…

Space Physics · Physics 2017-09-20 Terry Z. Liu , Vassilis Angelopoulos , Heli Hietala , Lynn B. Wilson

We present the particle-in-cell (PIC) simulation results of the interaction of a high-energy lepton plasma flow with background electron-proton plasma and focus on the acceleration processes of the protons. It is found that the acceleration…

High Energy Astrophysical Phenomena · Physics 2015-12-17 Yun-Qian Cui , Zheng-Ming Sheng , Quan-Ming Lu , Yu-Tong Li , Jie Zhang
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