Radial Profile and Confinement of Energetic Particles during NBI and ICRF Heating in LHD

The energetic ion distributions and confinements are studied in the LHD plasma applying a newly developed radial profile measurement system FICXS (Fast Ion Charge Exchange Spectroscopy) based on the Doppler shifted Balmer-alpha (Hα) emission from the energetic ions charge-exchanged with injected neutral beams. A clear difference is found in the Hα emission spectrum changing the magnetic configurations from the neoclassical optimized (Rax=3.53m) to the classical heliotron (Rax>3.75m) configuration. The radial profiles of energetic ion distributions during ICRF heating are also investigated by the pellet charge exchange (PCX) measurement. These results are compared with the GNET simulations, in which the drift kinetic equation is solved in 5-D phase space, and show relatively good agreements.