Sheared-flow stabilization (SFS) of Z-pinch kink modes (m=1) investigated with Vlasov-Maxwell Kinetic model

Z-pinch stability and stabilizing factors for kink (m=1) perturbation are investigated using the Vlasov-Maxwell kinetic model for ions and electrons. Kinetic modeling is crucial for capturing plasma physics associated with strong deviations from local thermodynamic equilibrium and other departures from MHD or fluid model approximations (e.g. low collisionality and finite Larmor radius). The continuum-kinetic simulations presented have achieved the pivotal computational task of six-dimensional phase-space and long time integration by large scale GPU emloyment.

This work presents 3d3v Z-pinch simulations performed with up to 6,912 GPUs on the Frontier, Perlmutter, and Summit supercomputers. The instability growth is evaluated and compared to existing publications from MHD and two-fluid modeling. Model approximations (e.g., artificial electron mass and speed of light) are employed to mitigate time-step limitations. An analysis of additional computation time needed to complete a comprehensive picture covering different perturbation wavenumber and sheared-flow rates is also provided.