Isotropic, homogeneous, incompressible fully developed turbulence in polar wind: observation of the inertial range

Theoretical results shows that, under the hypotheses of isotropy, local homogeneity and incompressibility, the high Reynolds number solar wind should present a linear scaling law for the pseudo-energy flux. This is the analogous of the celebrate 4/5 law for neutral fluids. Recent observations have shown that such range is indeed present in some streams of polar wind, as recorded by the Ulysses spacecraft. In this work we point out the main characteristics of the wind when the scaling is observed, in comparison with regions of non-scaling. Spectral properties shows that the role of the interplanetary magnetic field is crucial, as well as the compressibility of the wind.