Authors: Evan Yerger (Space Science Center), Benjamin Chandran (University of New Hampshire), Vincent David (Space Science Center), Romain Meyrand (Space Science Center/University of Otago)

Perpendicular proton heating has long been thought to be a necessary ingredient to explain the asymptotic speed of the fast solar wind. One potential mechanism for this heating is the thermalization of imbalanced Alfvenic turbulence launched by movements at the base of the corona. Despite a number of recent in situ observations of proton cyclotron heating in the solar wind, there is still much debate over how the cascade reaches the necessary kinetic scales. In this poster, we adopt a solar wind flux-tube model and fit its free parameters to model Parker Solar Probe encounter 10. We then motivate a model for imbalanced, reflection-driven turbulence, which we use to constrain the relative strength of proton-cyclotron heating as a function of distance away from the sun.