Application of Kinetic-Ion Magnetohydrodynamic Particle-in-Cell Modeling to Laboratory Plasmas

Single-fluid, (magneto)hydrodynamic, simulations are currently a workhorse simulation tool for modeling a wide range of plasma phenomena. These simulations assume quasi-neutral, Maxwellian plasmas describable by a generalized Ohm’s law. This simplifying assumption allows electron dynamics to be decoupled from the ion motion thereby reducing the required resolution (time/space) by factors of a thousand. It is this speed and numerical reliability that has made these codes irreplaceable tools for designing, optimizing and understanding plasma phenomena at the laboratory scale. However, these models do not intrinsically include many important kinetic effects, such as modification of transport coefficients due to electron kinetics, EM wave-interaction, flow interpenetration and ion-species separation. At the other limit, fully kinetic models, such as particle-in-cell (PIC) and Vlasov-Fokker-Planck codes, completely model electrons, ions and their coupling and thus intrinsically resolve such phenomena. However, in many cases due to computational expense, they must be run at subscale with reduced ion mass ratios, and often require millions of cpu-hrs. In this talk we present a middle ground between these two extremes, by using a multi-species, magnetized hydrodynamic model within the framework of the hybrid-PIC code Chicago [Thoma et al. PoP 24, 062707 (2017)]. This method follows the motion of (fluid or kinetic) ions and models electrons using a (magnetized) Ohm’s law. This tool is applicable in a wide range of regimes applicable to astrophysical collisionless shocks, interpenetration in near-vacuum hohlraums and in magnetized Z-pinch plasmas.