Further testing of anisotropic plasma turbulence theory with spacecraft observations of the solar wind

We use magnetic field observations from the fast solar wind made by the Ulysses, Wind, and Cluster spacecraft to measure the anisotropic scaling of the full power-spectra-tensor of inertial range turbulence in the solar wind. We use the results to make the most rigorous test of anisotropic turbulence theories thus far by solar wind observations. We compare the diagonal and off-diagonal terms of the tensor at different scales to reveal the different effects of sampling causing the projection of the anisotropic spectrum into the spacecraft observation frame. There is clear indication of anisotropy similar to "critical balance" in the inertial range, but the most striking result is the departure from the inertial range behavior observed at smaller scales in the "dissipation range".