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Title: Driven Resonance in Partially Relaxed Plasmas

Abstract

A Taylor-relaxed plasma (j=kB with k a constant) under external magnetic helicity injection encounters resonances in spatial frequencies of its force-free eigenmodes. Such driven resonance underlies the physics of magnetic self-organization and determines the flux amplification in laboratory helicity injection applications. Here we show that for partially relaxed plasmas where the deviation from the fully relaxed Taylor state, for example, a flux-dependent k, is a function of the normalized flux {chi}/{chi}{sub a} with {chi}{sub a} the poloidal flux at the magnetic axis, a modified driven resonance persists even if k({chi}) has an order-unity variation across the flux surfaces.

Authors:
 [1]
  1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
20951276
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevLett.98.175001; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLIFICATION; HELICITY; MAGNETIC SURFACES; PLASMA; RESONANCE

Citation Formats

Tang, X. Z.. Driven Resonance in Partially Relaxed Plasmas. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.175001.
Tang, X. Z.. Driven Resonance in Partially Relaxed Plasmas. United States. doi:10.1103/PHYSREVLETT.98.175001.
Tang, X. Z.. Fri . "Driven Resonance in Partially Relaxed Plasmas". United States. doi:10.1103/PHYSREVLETT.98.175001.
@article{osti_20951276,
title = {Driven Resonance in Partially Relaxed Plasmas},
author = {Tang, X. Z.},
abstractNote = {A Taylor-relaxed plasma (j=kB with k a constant) under external magnetic helicity injection encounters resonances in spatial frequencies of its force-free eigenmodes. Such driven resonance underlies the physics of magnetic self-organization and determines the flux amplification in laboratory helicity injection applications. Here we show that for partially relaxed plasmas where the deviation from the fully relaxed Taylor state, for example, a flux-dependent k, is a function of the normalized flux {chi}/{chi}{sub a} with {chi}{sub a} the poloidal flux at the magnetic axis, a modified driven resonance persists even if k({chi}) has an order-unity variation across the flux surfaces.},
doi = {10.1103/PHYSREVLETT.98.175001},
journal = {Physical Review Letters},
number = 17,
volume = 98,
place = {United States},
year = {Fri Apr 27 00:00:00 EDT 2007},
month = {Fri Apr 27 00:00:00 EDT 2007}
}
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