Omnidirectional Elsässer power spectra with respect to perpendicular wavenumber. The top and bottom panels correspond to radial distances of r/R⊙ = 6.46 and r/R⊙ = 17.3, respectively. Solid lines indicate the spectra of antisunward (E+, red) and sunward (E−, blue) Elsässer variables, respectively. Power-law-fitted lines in the inertial range are shown by the dashed lines.