Spectroscopy study of plasma particle equilibrium in the HL-1 tokamak

The carbonization of the vessel wall in the HL-1 tokamak is described. The particle confinement times of hydrogen and hydrogen recycling before/after carbonization, as well as those with pumping limiter, have been observed. The results show that, the hydrogen recycling with carbonization is increased; the use of a pumping limiter makes it possible to control the particle density of the edge plasma near the wall; the particle confinement time with the pumping limiter is 17.7% linger than that without the pumping limiter, and correspondingly, the recycling coefficient decreases by 13.2%