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Title: Detailed numerical investigation of 90∘ scattering of energetic particles interacting with magnetic turbulence

Abstract

In the present paper, we re-visit a well-known problem in diffusion theory, namely the 90∘ scattering problem. We use a test-particle code to compute the pitch-angle Fokker-Planck coefficient at 90∘ for different values of the turbulent magnetic field strength and the magnetic rigidity. We consider a slab model and compare our numerical findings with the analytical result provided by second-order quasilinear theory. We show that the latter theory accurately describes 90∘ scattering. We also replace the slab model by a more realistic two-component model to explore the influence of the turbulence model on 90∘ scattering.

Authors:
 [1];  [2]
  1. State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190 (China)
  2. Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)
Publication Date:
OSTI Identifier:
22253010
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; FOKKER-PLANCK EQUATION; MAGNETIC FIELDS; MAGNETIC RIGIDITY; QUASILINEAR PROBLEMS; SCATTERING; TEST PARTICLES; TURBULENCE

Citation Formats

Qin, G., and Shalchi, A. Detailed numerical investigation of 90∘ scattering of energetic particles interacting with magnetic turbulence. United States: N. p., 2014. Web. doi:10.1063/1.4873895.
Qin, G., & Shalchi, A. Detailed numerical investigation of 90∘ scattering of energetic particles interacting with magnetic turbulence. United States. doi:10.1063/1.4873895.
Qin, G., and Shalchi, A. Tue . "Detailed numerical investigation of 90∘ scattering of energetic particles interacting with magnetic turbulence". United States. doi:10.1063/1.4873895.
@article{osti_22253010,
title = {Detailed numerical investigation of 90∘ scattering of energetic particles interacting with magnetic turbulence},
author = {Qin, G. and Shalchi, A.},
abstractNote = {In the present paper, we re-visit a well-known problem in diffusion theory, namely the 90∘ scattering problem. We use a test-particle code to compute the pitch-angle Fokker-Planck coefficient at 90∘ for different values of the turbulent magnetic field strength and the magnetic rigidity. We consider a slab model and compare our numerical findings with the analytical result provided by second-order quasilinear theory. We show that the latter theory accurately describes 90∘ scattering. We also replace the slab model by a more realistic two-component model to explore the influence of the turbulence model on 90∘ scattering.},
doi = {10.1063/1.4873895},
journal = {Physics of Plasmas},
number = 4,
volume = 21,
place = {United States},
year = {Tue Apr 15 00:00:00 EDT 2014},
month = {Tue Apr 15 00:00:00 EDT 2014}
}
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