Studying sheath profiles using the Vlasov-Poisson system with the inclusion of Z-pinch wall currents

The shear flow stabilized Z-pinch has been studied as a lower cost, commercially viable, intermediate-scale thermonuclear fusion reactor. A study of sheath formation and dynamics in the presence of large Z-pinch axial currents into the wall remains an open research area. Simulations are performed using the continuum-kinetic model in the Gkeyll code. The 1X-1V Vlasov-Poisson system is used in parameter regimes of relevance to the FuZE (Fusion Z-pinch Experiment) as well as higher current regimes, through a parametric scan of various electron drift velocities. In a classical plasma sheath (with no axial current), the electrons are less dense at the wall than the ions. The electron density at the wall increases as a function of axial current; there is a critical current at which the electrons become more dense than the ions. For all cases considered, the axial current is maintained and the electrons dominate the particle and heat fluxes.