The Measurement of end Loss Ion Energy Distribution in Cusp of Hanbit Mirror Device

The end loss ion energy distributions are measured in Hanbit¹ mirror plasma produced by a 3.75-MHz, 500 kW° amplifiers with the slot antenna. The measurement of the ion energy distribution in the end region gives us the important information on the loss cone region of mirror plasmas.

The ion energy analyzer, mounted on the end region of cusp in the Hanbit, is versatile diagnostics designed to measure the parallel ion energy distributions. We can obtain the ion energy distribution from the current-voltage curve by sweeping the voltage on the ion repeller while keeping the other grids properly biased to repel the unwanted species. We show that the end loss ion currents, involved the magnetic confinement, vary according as the strength of magnetic field

We compared an end loss ion distribution obtained from the Hanbit with ion energy from DC discharge to test the analyzer.