Kinetic Alfvén waves from hybrid-Vlasov simulations

Kinetic Alfvén wave (KAW) is the kinetic extension of shear Alfvén wave (SAW) where the perpendicular wavelength with respect to the magnetic field becomes comparable to the ion scale. It has been suggested theoretically that mode conversion from incident compressional waves to KAWs at the magnetopause leads to the plasma transport. Existence of KAWs has been identified from in-situ observations and shown to be closely related to the Hall field from magnetic reconnection. In this study, we investigate the properties of KAWs using the hybrid-Vlasov model Vlasiator. Local runs of tangential discontinuities with parameters relevant to Earth’s magnetopause are performed to look at the mode conversion from fast waves to Alfvén waves. Signatures of KAWs are identified from both local and global simulations, which provide insights into the nonlinear plasma transport process in the magnetosphere.