Effect of the Divertor Leg Length on the Population of Molecular Ions in the Divertor Simulator TPD-SheetIV

In TPD-SheetIV, a simulation experiment on a long leg divertor configuration has been conducted and hydrogen molecular ion formation in detached plasma was observed. Improvements to the simulation geometry used in DEGAS 2 allowed us to study the effect of leg length on neutral transport. This paper also describes a simple ion balance equation and the ion density ratios obtained with it. From these data, it is shown that a long leg divertor enhances molecular ion density in the divertor, which might enhance molecular assisted recombination.