Hybrid Simulation Studies of Wave-Ion Interactions With Application to the Corona and Solar Wind

Strong ion heating and bulk flow acceleration is either inferred or directly observed in the corona and solar wind. A likely source of this heating and acceleration comes from Alfvénic fluctuations evolving turbulently and cascading wave energy to small scales where direct interactions with ions occur. We present a number of studies using a hybrid numerical simulation with particle ions and a quasineutralizing electron fluid. We examine several situations which could arise in turbulence. First, we examine a cascade among large-amplitude waves with imbedded abrupt field rotations called rotational discontinuities (RDs). This situation is appropriate to the solar wind. We show how the cascade and interactions with RDs can heat ions and also decelerate streaming populations of helium relative to protons. This deceleration of helium is observed in the solar wind. We then examine a class of partially driven simulations meant to mimic the dissipation range of turbulence in the corona and solar wind. Finally, we show simulation results of the reconnection or merger of magnetic fields and examine its effect on ions.