Particle Confinement of Limiter- and Divertor-Dominated NBI Plasmas in CHS

Particle confinement time {tau}{sub p} has been obtained from measurements of poloidal and toroidal distributions of H{alpha} and Lyman {alpha} emissions in CHS. These particle confinement times range between 1.5 and 4ms at a constant line-averaged density of 3 x 10{sup 13}cm{sup -3} for both cases of limiter- and divertor-dominated NBI plasmas with Ti-gettering. In these cases the energy confinement time {tau}{sub E} were between 2 and 3ms. The density decay characteristic time {tau}{sub p}{sup *} and global recycling coefficient R have been also measured for Ti-gettered plasmas and large {tau}{sub p}{sup *} values were observed. As a result high recycling rates (R>0.92) are obtained for a wide density range. For a limiter-dominated case of boronized plasmas (R{sub ax}=92.1cm) values of {tau}{sub p} were correlated with {tau}{sub E} and a linear correlation between them was found for normalized {tau}{sub E} to P{sup -0.58} which is a power degradation term in LHD empirical scaling. 6 refs., 9 figs.