High-fidelity kinetic modeling of instabilities in nonuniform low-beta finite-gyromotion plasmas

Performance and scalability of pulsed power inertial confinement fusion experiments are strongly influenced by the kinetic physics of low-beta collisionless plasmas.  Such plasmas are produced at electrode surfaces of power feeds, which deliver mega-amps of current to a Z-pinch load and which feature an ExB environment.  Through unexplained transport mechanisms, these plasmas lead to parasitic currents and can contaminate the load.  To shed light on how kinetic processes influence macroscopic transport properties, a high-fidelity kinetic modeling approach is employed.  The methodology is based on a fourth-order finite-volume continuum kinetic Vlasov solver and a systematic method for constructing customizable two-species kinetic equilibria.  The quiet-start noise-free approach is applied to investigate Kelvin-Helmholtz and lower hybrid drift instabilities in 4D (x,y,v_x,v_y) phase space.  Configurations where ion gyroradii are comparable to gradient scale lengths are investigated.  Distribution function structures, energy partitioning, and finite Larmor radius effects are explored in detail.  The methodology opens the way for targeted high-accuracy computational studies of plasma configurations where gyromotion plays an important role.  LLNL-ABS-824101