Simultaneous measurements of electron density and its fluctuations were performed successfully in the CHS edge plasma during the L-H transition with a thermal neutral lithium beam probe. Very rapid formation of edge particle transport barrier within 0.1 msec was observed at the L-H transition, i.e., steepening of the edge electron density profile and reduction of the outward particle flux. The reduction of the fluctuation amplitude was also observed in the edge region, which was thought to be related to the formation of the edge particle transport barrier.
- Edge plasma
- Edge transport barrier
- L-H transition
- Thermal neutral lithium beam probe