Global existence of plasma ion-sheaths and their dynamics
The authors study simplified Euler-Poisson systems (E-P) describing the motion of plasma sheaths in a plasma consisting of ions and electrons. Their goal is to describe the dynamics of the plasma in both the quasi-neutral and sheath regions. The simplification of (E-P) uses symmetries, planar geometry, and scaling adjusted to the physical problem. The problem is formulated as a free boundary value problem, and the simplified (E-P) is subject to initial and boundary conditions on a bounded domain which is decomposed into two subdomains (a `quasi-neutral region' and a `sheath region'). On each subdomain a specialized version of (E-P) is considered according to suitable physical situations. Under certain regularity assumptions the authors prove the existence of global solutions of the `ion sheath system' using a characteristic method whereas the study of the dynamics of the `plasma sheath system' uses ODEs.
scientific article; zbMATH DE number 2018514