Anisotropic Scaling of Magnetohydrodynamic Turbulence

Journal Article · Fri Oct 24 04:00:00 EDT 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.101.175005· OSTI ID:21179849

Horbury, Timothy S; Forman, Miriam; Oughton, Sean ^[1]

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1. Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom)

We present a quantitative estimate of the anisotropic power and scaling of magnetic field fluctuations in inertial range magnetohydrodynamic turbulence, using a novel wavelet technique applied to spacecraft measurements in the solar wind. We show for the first time that, when the local magnetic field direction is parallel to the flow, the spacecraft-frame spectrum has a spectral index near 2. This can be interpreted as the signature of a population of fluctuations in field-parallel wave numbers with a k{sub parallel}{sup -2} spectrum but is also consistent with the presence of a 'critical balance' style turbulent cascade. We also find, in common with previous studies, that most of the power is contained in wave vectors at large angles to the local magnetic field and that this component of the turbulence has a spectral index of 5/3.

• OSTI ID: 21179849
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 17 Vol. 101; 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
ANISOTROPY
FLUCTUATIONS
MAGNETIC FIELDS
SOLAR WIND
SPECTRA
TURBULENCE
VECTORS