Observational Constraints on the Role of Kinetic Alfven Waves in the Solar Wind

Several recent publications have proposed an extreme view of ion inertial and dissipation range dynamics that can be readily tested. Specifically, a view has been proposed by Alexandrova et al. (2009) that suggests a second turbulent inertial range may exist at scales smaller than the ion inertial scale where electron MHD dynamics may provide energy transport without dissipation. This leads to a predictable and reproducible spectrum at spacecraft frame frequencies greater than the proton cyclotron frequency and less than the electron cyclotron frequency. However, other very radical interpretations of the observations have suggested that highly perpendicular Kinetic Alfven Waves (KAW) can be used to describe the ion inertial scales through these high frequencies and extending to the electron cyclotron frequency such that the high frequency measurements are just Doppler shifted extensions of this highly perpendicular inertial range dynamics (Sahraoui et al. 2009, 2010). We take exception to these interpretations and provide a series of observational tests that clearly refute the arguments.