Evidence of a Cascade and Dissipation of Solar-Wind Turbulence at the Electron Gyroscale
Publication date: 11 June 2009
Authors: Sahraoui, F. et al. 2009
Journal: Phys. Rev. Lett.
Copyright: The American Physical Society
We report the first direct determination of the dissipation range of magnetofluid turbulence in the solar wind at the electron scales. Combining high resolution magnetic and electric field data of the Cluster spacecraft, we computed the spectrum of turbulence and found two distinct breakpoints in the magnetic spectrum at 0.4 and 35 Hz, which correspond, respectively, to the Doppler-shifted proton and electron gyroscales, frho_p and frho_e. Below frho_p, the spectrum follows a Kolmogorov scaling f -1.62, typical of spectra observed at 1 AU. Above frho_p, a second inertial range is formed with a scaling f -2.3 down to frho_e. Above frho_e, the spectrum has a steeper power law