PIC modeling of negative ion extraction from a dust-seeded plasma

Plasma behavior near the plasma grid of Negative Ion (NI) sources is studied by a 3D-electrostatic Particle-In-Cell (PIC) code. The computational domain is assumed to be a cuboid volume around a single hole of the plasma grid. The plasma is assumed to be seeded with Cs coated dusts that provides additional surfaces for NI production throughout the volume of the source. The dusts are not explicitly modeled; rather, constant charges are assumed to remain distributed randomly throughout the volume of the plasma mimicking the dust particles. The effect of dust on NI extraction is studied by considering its effect on controlling parameters like meniscus formation for different combination of the system variables. (author)