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Title: Chaotic magnetic fields: Particle motion and energization

Abstract

Magnetic field line equations correspond to a Hamiltonian dynamical system, so the features of a Hamiltonian systems can easily be adopted for discussing some essential features of magnetic field lines. The integrability of the magnetic field line equations are discussed by various authors and it can be shown that these equations are, in general, not integrable. We demonstrate several examples of realistic chaotic magnetic fields, produced by asymmetric current configurations. Particular examples of chaotic force-free field and non force-free fields are shown. We have studied, for the first time, the motion of a charged particle in chaotic magnetic fields. It is found that the motion of a charged particle in a chaotic magnetic field is not necessarily chaotic. We also showed that charged particles moving in a time-dependent chaotic magnetic field are energized. Such energization processes could play a dominant role in particle energization in several astrophysical environments including solar corona, solar flares and cosmic ray propagation in space.

Authors:
 [1];  [2];  [3];  [4]
  1. CSPAR, University of Alabama in Huntsville, Huntsville, AL 35805 (United States)
  2. Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
  3. Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 and CSPAR, University of Alabama in Huntsville, Huntsville, AL 35805 (United States)
  4. Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)
Publication Date:
OSTI Identifier:
22263920
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1582; Journal Issue: 1; Conference: International conference on complex processes in plasmas and nonlinear dynamical systems, Gandhinagar (India), 6-9 Nov 2012; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHARGED PARTICLES; COSMIC RAY PROPAGATION; EQUATIONS; HAMILTONIANS; MAGNETIC FIELDS; PARTICLES; SOLAR CORONA; SOLAR FLARES; TIME DEPENDENCE

Citation Formats

Dasgupta, Brahmananda, Ram, Abhay K., Li, Gang, and Li, Xiaocan. Chaotic magnetic fields: Particle motion and energization. United States: N. p., 2014. Web. doi:10.1063/1.4865359.
Dasgupta, Brahmananda, Ram, Abhay K., Li, Gang, & Li, Xiaocan. Chaotic magnetic fields: Particle motion and energization. United States. doi:10.1063/1.4865359.
Dasgupta, Brahmananda, Ram, Abhay K., Li, Gang, and Li, Xiaocan. 2014. "Chaotic magnetic fields: Particle motion and energization". United States. doi:10.1063/1.4865359.
@article{osti_22263920,
title = {Chaotic magnetic fields: Particle motion and energization},
author = {Dasgupta, Brahmananda and Ram, Abhay K. and Li, Gang and Li, Xiaocan},
abstractNote = {Magnetic field line equations correspond to a Hamiltonian dynamical system, so the features of a Hamiltonian systems can easily be adopted for discussing some essential features of magnetic field lines. The integrability of the magnetic field line equations are discussed by various authors and it can be shown that these equations are, in general, not integrable. We demonstrate several examples of realistic chaotic magnetic fields, produced by asymmetric current configurations. Particular examples of chaotic force-free field and non force-free fields are shown. We have studied, for the first time, the motion of a charged particle in chaotic magnetic fields. It is found that the motion of a charged particle in a chaotic magnetic field is not necessarily chaotic. We also showed that charged particles moving in a time-dependent chaotic magnetic field are energized. Such energization processes could play a dominant role in particle energization in several astrophysical environments including solar corona, solar flares and cosmic ray propagation in space.},
doi = {10.1063/1.4865359},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1582,
place = {United States},
year = 2014,
month = 2
}
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