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We present laboratory results on energy partitioning from supercritical, magnetized collisionless shock experiments ($\rm{M_A} \sim 8$, $\rm{M_{ms}}\sim 4$). We report the first observation of fully-developed laboratory shocks that evolve…

Shock waves associated with shell type supernova remnants are considered to be possible sites of cosmic ray acceleration. Since shocks are capable of accelerating electrons in addition to protons one anticipates both species to contribute…

Astrophysics · Physics 2011-05-23 A. Mastichiadis

Collisionless plasma shock theory, which applies for example to the afterglow of gamma ray bursts, still contains key issues that are poorly understood. In this paper we study charged particle dynamics in a highly relativistic collisionless…

Astrophysics · Physics 2009-11-10 C. B. Hededal , T. Haugboelle , J. Trier Frederiksen , Å. Nordlund

We show that it is possible to measure Alfv\'enic Mach numbers, defined as the shock velocity in the flow divided by the Alfv\'en velocity, for low-velocity (V$_{shock}$ $\lesssim$ 100 km$\,$s$^{-1}$) radiative shocks. The method combines…

Instrumentation and Methods for Astrophysics · Physics 2015-09-23 P. Hartigan , A. Wright

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

The present work considers a plane shock front propagating along a cylindrical jet. Electrons experience the diffusive shock acceleration around the shock front, and subsequently drift away into the downstream flow in which they emit most…

High Energy Astrophysical Phenomena · Physics 2018-07-04 Y. G. Zheng , G. B. Long , C. Y. Yang , J. M. Bai

Relativistic particle acceleration in collisionless shocks of supernova remnants is accompanied by magnetic field amplification from cosmic ray (CR) driven plasma instabilities. Bell's fast CR-current instability is predicted to produce…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Sergei M Osipov , Andrei M Bykov , Donald C Ellison

Intense laser-plasma interactions are an essential tool for the laboratory study of ion acceleration at a collisionless shock. With two-dimensional particle-in-cell calculations of a multicomponent plasma we observe two electrostatic…

We use large hybrid simulations to study ion acceleration and generation of magnetic turbulence due to the streaming of particles that are self-consistently accelerated at non-relativistic shocks. When acceleration is efficient, we find…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Damiano Caprioli , Anatoly Spitkovsky

In this paper, we study shock structures of collisionless shocks in partially ionized plasmas by means of two-dimensional hybrid simulations, where the shock is a perpendicular shock with shock velocity Vsh ~ 40 Va ~ 1333 km/s and the…

High Energy Astrophysical Phenomena · Physics 2016-02-03 Yutaka Ohira

We explore nonlinear effects of wave-particle interactions on the diffusive shock acceleration (DSA) process in Type Ia-like, SNR blast waves, by implementing phenomenological models for magnetic field amplification, Alfv'enic drift, and…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Hyesung Kang , T. W. Jones , Paul P. Edmon

Collisionless shock acceleration of protons and C$^{6+}$ ions has been achieved by the interaction of a 10$^{20}$ W/cm$^2$, 1 $\mu$m laser with a near-critical density plasma. Ablation of the initially solid density target by a secondary…

In the Universe matter outside of stars and compact objects is mostly composed of collisionless plasma. The interaction of a supersonic plasma flow with an obstacle results in collisionless shocks that are often associated with intense…

Plasma Physics · Physics 2022-05-18 Artem Bohdan , Martin S. Weidl , Paul J. Morris , Martin Pohl

The selfconsistent steady state solution for a strong shock, significantly modified by accelerated particles is obtained on the level of a kinetic description, assuming Bohm-type diffusion. The original problem that is commonly formulated…

Astrophysics · Physics 2009-10-30 M. A. Malkov

Recent X-ray observations of merger shocks in galaxy clusters have shown that the post-shock plasma is two-temperature, with the protons being hotter than the electrons. In this work, the second of a series, we investigate by means of…

High Energy Astrophysical Phenomena · Physics 2018-05-23 Xinyi Guo , Lorenzo Sironi , Ramesh Narayan

We investigate the process of Diffusive Shock Acceleration (DSA) of particles with mass number to charge number ratios $A/Q > 1$, e.g., partially-ionized heavy ions. To this end, we introduce helium- and carbon-like ions at solar abundances…

High Energy Astrophysical Phenomena · Physics 2025-10-31 Damiano Caprioli , Luca Orusa , Miha Cernetic , Colby C. Haggerty , Bricker Ostler

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…

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

It is argued and demonstrated by particle-in-cell simulations that the synchrotron maser instability could develop at the front of a relativistic, magnetized shock. The instability generates strong low-frequency electromagnetic waves…

Astrophysics · Physics 2008-11-26 Yuri Lyubarsky

I investigate the shape of the electron cosmic ray spectrum in the range up to ~1000 keV, assuming that the acceleration process at the shock results in a power law in momentum, and that downstream of the shock the spectrum is affected by…

Astrophysics · Physics 2008-06-30 Jacco Vink