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Title: Particle energization during solar maximum: Diffusive shock acceleration at multiple shocks

Abstract

We present a model for the acceleration of particles at multiple shocks using an approach related to box models. A distribution of particles is diffusively accelerated inside the box while simultaneously experiencing decompression through adiabatic expansion and losses from the convection and diffusion of particles out of the box by either the method used in Melrose and Pope and Pope and Melrose or by the approach introduced in Zank et al. where we solve the transport equation by a method analogous to operator splitting. The second method incorporates the additional loss terms of convection and diffusion and allows for the use of a variable time between shocks. We use a maximum injection energy (E{sub max}) appropriate for quasi-parallel and quasi-perpendicular shocks. We provide a preliminary application of the diffusive acceleration of particles by multiple shocks with frequencies appropriate for solar maximum.

Authors:
;  [1]
  1. Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States)
Publication Date:
OSTI Identifier:
22365443
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 790; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; BOX MODELS; CONVECTION; DIFFUSION; DISTRIBUTION; EXPANSION; INJECTION; LOSSES; MATHEMATICAL MODELS; PLASMA; SHOCK WAVES; SIMULATION; SOLAR PARTICLES; SOLAR WIND; SUN; TRANSPORT THEORY

Citation Formats

Neergaard Parker, L., and Zank, G. P., E-mail: linda.parker@uah.edu. Particle energization during solar maximum: Diffusive shock acceleration at multiple shocks. United States: N. p., 2014. Web. doi:10.1088/0004-637X/790/2/153.
Neergaard Parker, L., & Zank, G. P., E-mail: linda.parker@uah.edu. Particle energization during solar maximum: Diffusive shock acceleration at multiple shocks. United States. doi:10.1088/0004-637X/790/2/153.
Neergaard Parker, L., and Zank, G. P., E-mail: linda.parker@uah.edu. Fri . "Particle energization during solar maximum: Diffusive shock acceleration at multiple shocks". United States. doi:10.1088/0004-637X/790/2/153.
@article{osti_22365443,
title = {Particle energization during solar maximum: Diffusive shock acceleration at multiple shocks},
author = {Neergaard Parker, L. and Zank, G. P., E-mail: linda.parker@uah.edu},
abstractNote = {We present a model for the acceleration of particles at multiple shocks using an approach related to box models. A distribution of particles is diffusively accelerated inside the box while simultaneously experiencing decompression through adiabatic expansion and losses from the convection and diffusion of particles out of the box by either the method used in Melrose and Pope and Pope and Melrose or by the approach introduced in Zank et al. where we solve the transport equation by a method analogous to operator splitting. The second method incorporates the additional loss terms of convection and diffusion and allows for the use of a variable time between shocks. We use a maximum injection energy (E{sub max}) appropriate for quasi-parallel and quasi-perpendicular shocks. We provide a preliminary application of the diffusive acceleration of particles by multiple shocks with frequencies appropriate for solar maximum.},
doi = {10.1088/0004-637X/790/2/153},
journal = {Astrophysical Journal},
number = 2,
volume = 790,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2014},
month = {Fri Aug 01 00:00:00 EDT 2014}
}
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