Particle-in-cell simulations of circularly polarised Alfvén wave phase mixing: A new mechanism for electron acceleration in collisionless plasmas
Tsiklauri, D, Sakai, JI and Saito, S 2005, 'Particle-in-cell simulations of circularly polarised Alfvén wave phase mixing: A new mechanism for electron acceleration in collisionless plasmas' , Astronomy and Astrophysics, 435 (3) , pp. 1105-1113.
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In this work we used Particle-In-Cell simulations to study the interaction of circularly polarised Alhén waves with one dimensional plasma density inhomogeneities transverse to the uniform magnetic field (phase mixing) in collisionless plasmas. In our preliminary work we reported discovery of a new electron acceleration mechanism, in which progressive distortion of the Alfvén wave front, due to the differences in local Alfvén speed, generates an oblique (nearly parallel to the magnetic field) electrostatic field. The latter accelerates electrons through the Landau resonance. Here we report a detailed study of this novel mechanism, including: (i) analysis of broadening of the ion distribution function due to the presence of Alfvén waves; and (ii) the generation of compressive perturbations due to both weak non-linearity and plasma density inhomogeneity. The amplitude decay law in the inhomogeneous regions, in the kinetic regime, is demonstrated to be the same as in the MHD approximation described by Heyvaerts & Priest (1983, A&A, 117, 220).
|Uncontrolled Keywords:||Solar wind, sun, nonlinearity, disturbances, ion distribution, resonance, wave front, magnetic fields, plasma density, collisionless plasma, plasma acceleration, particle acceleration, mixing, alfven waves, polarized wave, circular polarization, particle code|
|Themes:||Subjects / Themes > Q Science > QB Astronomy > QB460 Astrophysics
Subjects / Themes > Q Science > QB Astronomy
Subjects outside of the University Themes
|Schools:||Schools > School of Computing, Science and Engineering|
|Journal or Publication Title:||Astronomy and Astrophysics|
|Depositing User:||H Kenna|
|Date Deposited:||23 Aug 2007 13:49|
|Last Modified:||01 Dec 2015 00:01|
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