Particle Pinch in Gyrokinetic Simulations of Closed Field-Line Systems

Journal Article · Fri Dec 03 04:00:00 EST 2010 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.105.235004· OSTI ID:21554449

Kobayashi, Sumire; Rogers, Barrett N; Dorland, William ^[1]

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1. Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

Gyrokinetic simulations of small-scale turbulent transport in a closed magnetic field-line plasma geometry are presented. The simulations are potentially applicable to dipolar systems such as the levitated dipole experiment (LDX) [J. Kesner et al., Plasma Phys. Rep. 23, 742 (1997)] and planetary magnetospheres, as well as simpler systems such as the Z pinch. We report here for the first time the existence of a robust particle (and weaker temperature) pinch regime, in which the particles are transported up the density gradient. The particle pinch is driven by non-MHD entropy-mode turbulence at k{sub perpendicular{rho}i}{approx}1 and particle pinch appears at larger {eta}{identical_to}L{sub n}/L{sub T} > or approx. 0.7, consistent with quasilinear theory. Our results suggest that entropy-mode transport will drive the LDX plasma profiles toward a state with {eta}{approx}0.7 and pressure gradients that are near marginal ideal MHD interchange-mode stability.

• OSTI ID: 21554449
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 23 Vol. 105; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
DENSITY
DIPOLES
ENTROPY
FLUID MECHANICS
GEOMETRY
HYDRODYNAMICS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MATHEMATICS
MECHANICS
MULTIPOLES
PHYSICAL PROPERTIES
PLANETARY ATMOSPHERES
PLANETARY MAGNETOSPHERES
PLASMA
PLASMA RADIAL PROFILES
PRESSURE GRADIENTS
QUASILINEAR PROBLEMS
SIMULATION
STABILITY
THERMODYNAMIC PROPERTIES
TURBULENCE