Measurements of NBI and ion cyclotron range of frequency power deposition profiles using charge exchange spectroscopy

Abstract
Power deposition profiles of a heating neutral beam and/or an ion cyclotron range of frequency (ICRF) heating have been measured on the JIPP T‐IIU tokamak. The deposition is obtained from the rise time of the ion temperature, which is measured from the Doppler broadening of C vi emission produced by charge exchange reaction between a neutral beam and a carbon impurity. The power deposition of ICRF has been found to be flatter than that of neutral beam injection (NBI). The thermal diffusivities are 4–5 times larger than the neoclassical values both in NBI and NBI+ICRF cases.