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Title: Wakefield Acceleration in Relativistic Plasma Flows: Electron Acceleration to Cosmic Ray Energies

Abstract

Energetic particles observed in astrophysical environments imply the existence of efficient particle accelerators. These accelerators could be driven by relativistically colliding plasma. Collisionless plasmas thermalize through the growth of electromagnetic and electrostatic waves and the subsequent wave-particle interactions. Kinetic interactions are potentially important in this context, since they can transfer significant energy to limited plasma phase space intervals and they thus constitute energy-efficient accelerators. Kinetic processes relevant to astroplasma physics can be modelled by relativistic particle-in-cell simulations. Here we revise this simulation method and apply it to ion-beam driven plasma wave accelerators that may be involved in the thermalization of supernova remnant shocks and the internal shocks of relativistic astrophysical jets.

Authors:
 [1];  [2];  [3]
  1. Department of Science and Technology (ITN), Linkoping University, Campus Norrkoping, SE-60174 Norrkoping (Sweden)
  2. (Germany)
  3. Institute of Theoretical Physics IV, Ruhr-University Bochum, D-44780 Bochum (Germany)
Publication Date:
OSTI Identifier:
21057321
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 906; Journal Issue: 1; Conference: Stockholm symposium on GRB's: Gamma-ray bursts prospects for GLAST, Stockholm (Sweden), 1 Sep 2006; Other Information: DOI: 10.1063/1.2737407; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; ASTROPHYSICS; COLLISIONLESS PLASMA; COMPUTERIZED SIMULATION; COSMIC GAMMA SOURCES; COSMIC RADIATION; ELECTRONS; ION BEAMS; PARTICLE INTERACTIONS; PHASE SPACE; PLASMA WAVES; RELATIVISTIC PLASMA; RELATIVISTIC RANGE; SUPERNOVA REMNANTS; THERMALIZATION; WAKEFIELD ACCELERATORS

Citation Formats

Dieckmann, Mark E., Institute of Theoretical Physics IV, Ruhr-University Bochum, D-44780 Bochum, and Shukla, Padma K. Wakefield Acceleration in Relativistic Plasma Flows: Electron Acceleration to Cosmic Ray Energies. United States: N. p., 2007. Web. doi:10.1063/1.2737407.
Dieckmann, Mark E., Institute of Theoretical Physics IV, Ruhr-University Bochum, D-44780 Bochum, & Shukla, Padma K. Wakefield Acceleration in Relativistic Plasma Flows: Electron Acceleration to Cosmic Ray Energies. United States. doi:10.1063/1.2737407.
Dieckmann, Mark E., Institute of Theoretical Physics IV, Ruhr-University Bochum, D-44780 Bochum, and Shukla, Padma K. Tue . "Wakefield Acceleration in Relativistic Plasma Flows: Electron Acceleration to Cosmic Ray Energies". United States. doi:10.1063/1.2737407.
@article{osti_21057321,
title = {Wakefield Acceleration in Relativistic Plasma Flows: Electron Acceleration to Cosmic Ray Energies},
author = {Dieckmann, Mark E. and Institute of Theoretical Physics IV, Ruhr-University Bochum, D-44780 Bochum and Shukla, Padma K.},
abstractNote = {Energetic particles observed in astrophysical environments imply the existence of efficient particle accelerators. These accelerators could be driven by relativistically colliding plasma. Collisionless plasmas thermalize through the growth of electromagnetic and electrostatic waves and the subsequent wave-particle interactions. Kinetic interactions are potentially important in this context, since they can transfer significant energy to limited plasma phase space intervals and they thus constitute energy-efficient accelerators. Kinetic processes relevant to astroplasma physics can be modelled by relativistic particle-in-cell simulations. Here we revise this simulation method and apply it to ion-beam driven plasma wave accelerators that may be involved in the thermalization of supernova remnant shocks and the internal shocks of relativistic astrophysical jets.},
doi = {10.1063/1.2737407},
journal = {AIP Conference Proceedings},
number = 1,
volume = 906,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • The ever increasing performance of supercomputers is now enabling kinetic simulations of extreme astrophysical and laser produced plasmas. Three-dimensional particle-in-cell (PIC) simulations of relativistic shocks have revealed highly filamented spatial structures and their ability to accelerate particles to ultrarelativistic speeds. However, these PIC simulations have not yet revealed mechanisms that could produce particles with tera-electron volt energies and beyond. In this work, PIC simulations in one dimension (1D) of the foreshock region of an internal shock in a gamma ray burst are performed to address this issue. The large spatiotemporal range accessible to a 1D simulation enables the self-consistent evolutionmore » of proton phase space structures that can accelerate particles to giga-electron volt energies in the jet frame of reference, and to tens of tera-electron volt in the Earth's frame of reference. One potential source of ultrahigh energy cosmic rays may thus be the thermalization of relativistically moving plasma.« less
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  • Electron beams with hundreds of picoCoulombs of charge in percent energy spread at above 80 MeV, and with few milliradian divergence, have been produced for the first time in a high gradient laser wakefield accelerator by guiding the drive laser pulse. Channels formed by hydrodynamic shock were used to guide acceleration relevant laser intensities of at least 1E18 W/cm2 at the guide output over more than 10 Rayleigh lengths at LBNL's l'OASIS facility (10 TW, 2E19 W/cm2). The pondermotive force of the laser pulse drove an intense plasma wave, producing acceleration gradients on the order of 100 GV/m. Electrons weremore » trapped from the background plasma and accelerated. By extending the acceleration length using the guiding channel, the energy of the electron beam was greatly increased, and bunches of small energy spread and low emittance were formed. Experiments varying gas jet length as well as simulations indicate that the high quality beams were formed when beam loading turned off injection after an initial load, producing an isolated bunch, and when that bunch was subsequently accelerated to the dephasing length at which point it rotated in phase space to produce low energy spread.« less
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