Spectrum of Magnetohydrodynamic Turbulence

Journal Article · Fri Mar 24 04:00:00 EST 2006 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.96.115002· OSTI ID:20777108

Boldyrev, Stanislav ^[1]

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1. Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637 (United States)

We propose a phenomenological theory of strong incompressible magnetohydrodynamic turbulence in the presence of a strong large-scale external magnetic field. We argue that in the inertial range of scales, magnetic-field and velocity-field fluctuations tend to align the directions of their polarizations. However, the perfect alignment cannot be reached; it is precluded by the presence of a constant energy flux over scales. As a consequence, the directions of shear-Alfven fluid and magnetic-field fluctuations at each scale {lambda} become effectively aligned within the angle {phi}{sub {lambda}}{proportional_to}{lambda}{sup 1/4}, which leads to scale-dependent depletion of the nonlinear interaction and to the field-perpendicular energy spectrum E(k{sub perpendicular}){proportional_to}k{sub perpendicular}{sup -3/2}. Our results may be universal, i.e., independent of the external magnetic field, since small-scale fluctuations locally experience a strong field produced by large-scale eddies.

• OSTI ID: 20777108
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 11 Vol. 96; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ENERGY SPECTRA
FLUCTUATIONS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
NONLINEAR PROBLEMS
PLASMA
POLARIZATION
TURBULENCE