THE INFLUENCE OF INTERMITTENCY ON THE SPECTRAL ANISOTROPY OF SOLAR WIND TURBULENCE
- School of Earth and Space Sciences, Peking University, 100871 Beijing (China)
- Institute for Experimental and Applied Physics, Christian Albrechts University at Kiel, D-24118 Kiel (Germany)
The relation between the intermittency and the anisotropy of the power spectrum in the solar wind turbulence is studied by applying the wavelet technique to the magnetic field and flow velocity data measured by the WIND spacecraft. It is found that when the intermittency is removed from the turbulence, the spectral indices of the power spectra of the field and velocity turn out to be independent of the angle θ{sub RB} between the direction of the local scale-dependent background magnetic field and the heliocentric direction. The spectral index becomes –1.63 ± 0.02 for magnetic field fluctuations and –1.56 ± 0.02 for velocity fluctuations. These results may suggest that the recently found spectral anisotropy of solar wind power spectra in the inertial range could result from turbulence intermittency. As a consequence, a new concept is here proposed of an intermittency-associated sub-range of the inertial domain adjacent to the dissipation range. Since spectral anisotropy was previously explained as evidence for the presence of a ''critical balance'' type turbulent cascade, and also for the existence of kinetic Alfvén waves, this new finding may stimulate fresh thoughts on how to analyze and interpret solar wind turbulence and the associated heating.
- OSTI ID:
- 22363964
- Journal Information:
- Astrophysical Journal Letters, Vol. 783, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of Intermittency on the Quasi-perpendicular Scaling in Three-dimensional Magnetohydrodynamic Turbulence
POWER ANISOTROPY IN THE MAGNETIC FIELD POWER SPECTRAL TENSOR OF SOLAR WIND TURBULENCE