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Title: Small-Scale Turbulence in a Closed-Field-Line Geometry

Abstract

Plasma turbulence due to small-scale entropy modes is studied with gyrokinetic simulations in a simple closed-field-line geometry, the Z pinch, in low-{beta} parameter regimes that are stable to ideal interchange modes. We find an enormous variation in the nonlinear dynamics and particle transport as a function of two main parameters, the density gradient and the plasma collisionality. This variation is explained in part by the damping and stability properties of spontaneously formed zonal flows in the system. As in toroidal systems, the zonal flows can lead to a strong nonlinear suppression of transport below a critical gradient that is determined by the stability of the zonal flows.

Authors:
; ;  [1];  [2]
  1. Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20861483
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 97; Journal Issue: 24; Other Information: DOI: 10.1103/PhysRevLett.97.245001; (c) 2006 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; CHARGED-PARTICLE TRANSPORT; ENTROPY; GEOMETRY; NONLINEAR PROBLEMS; PLASMA; SIMULATION; STABILITY; TURBULENCE; VARIATIONS

Citation Formats

Ricci, Paolo, Rogers, B. N., Dorland, W., and Department of Physics, University of Maryland, College Park, Maryland 20742. Small-Scale Turbulence in a Closed-Field-Line Geometry. United States: N. p., 2006. Web. doi:10.1103/PHYSREVLETT.97.245001.
Ricci, Paolo, Rogers, B. N., Dorland, W., & Department of Physics, University of Maryland, College Park, Maryland 20742. Small-Scale Turbulence in a Closed-Field-Line Geometry. United States. doi:10.1103/PHYSREVLETT.97.245001.
Ricci, Paolo, Rogers, B. N., Dorland, W., and Department of Physics, University of Maryland, College Park, Maryland 20742. Fri . "Small-Scale Turbulence in a Closed-Field-Line Geometry". United States. doi:10.1103/PHYSREVLETT.97.245001.
@article{osti_20861483,
title = {Small-Scale Turbulence in a Closed-Field-Line Geometry},
author = {Ricci, Paolo and Rogers, B. N. and Dorland, W. and Department of Physics, University of Maryland, College Park, Maryland 20742},
abstractNote = {Plasma turbulence due to small-scale entropy modes is studied with gyrokinetic simulations in a simple closed-field-line geometry, the Z pinch, in low-{beta} parameter regimes that are stable to ideal interchange modes. We find an enormous variation in the nonlinear dynamics and particle transport as a function of two main parameters, the density gradient and the plasma collisionality. This variation is explained in part by the damping and stability properties of spontaneously formed zonal flows in the system. As in toroidal systems, the zonal flows can lead to a strong nonlinear suppression of transport below a critical gradient that is determined by the stability of the zonal flows.},
doi = {10.1103/PHYSREVLETT.97.245001},
journal = {Physical Review Letters},
number = 24,
volume = 97,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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