Study of the operational region with new graphite limiters in the Hefei tokamak-7

Abstract

A new set of actively cooled toroidal double-ring graphite limiters has been developed in the Hefei tokamak-7 for long pulse operation. The extension of the operational region and the density behaviour with graphite limiters have been studied in this paper. An extended high-density region at high plasma currents and low q a was obtained. The density profile with graphite limiters was studied in order to compare the results with those of the previous molybdenum limiters.