ON ION EXTRACTION FROM A LOW-DENSITY PLASMA THROUGH GRID MESHES

Ion extraction is one of the main problems in laser isotope separation with the use of the AVLIS (atomic vapor laser isotope separation) tec hnique. We model a collector in the form of grids inducing fields that accelerate ions and decelerate electrons. The passage of a collisionl ess laser-produced plasma through a mesh of a grid extracting ions is considered in terms of a two-dimensional stationary problem. It is dem onstrated that, with moderate field strengths, electrons are efficient ly displaced by the electric field and do not reach the first grid, ha ving a zero potential. The ion transmittance of grids is mainly determ ined by geometric factors.