2008/07/23 by T. S. Horbury, M. A. Forman, S. Oughton · 10 citations
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Anisotropy #Astronomy #Classical mechanics #Computational physics #Field (mathematics) #Geomagnetism and Paleomagnetism Studies #Geometry #Ionosphere and magnetosphere dynamics #Magnetic field #Magnetohydrodynamic drive #Magnetohydrodynamic turbulence #Magnetohydrodynamics #Mechanics #Optics #Physics #Scaling #Solar and Space Plasma Dynamics #Solar wind #Spectral density #Spectral index #Spectral line #Turbulence #physics.plasm-ph #physics.space-ph
paper · pdf · doi:10.1103/physrevlett.101.175005
arxiv created 2008/07/23 · openalex publication_date 2008/10/24 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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(-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.