Fe14+ and Fe15+ spatial distributions in a LHD plasma reconstructed from multiple-viewing-chord EUV-emission observation

We have observed Fe14+ (3s21S0 - 3s3p 1P1) and Fe15+ (3s 2S1/2 - 3p 2P3/2) emissions from a LHD plasma with a space-resolved extreme-ultraviolet spectrometer. The observed intensity distributions against the viewing chord for the respective emissions are reconstructed to the emission flux distributions in the plasma against the normalized radius of the poloidal cross section with a maximum entropy method. Both of the emissions localize in the periphery region, and the Fe14+ emission is located outer side than that of Fe15+. We calculate the charge state distribution of Fe ions against the normalized radius assuming the ionization equilibrium at the electron temperature and density, which are measured by a Thomson scattering method. The calculated result is consistent with the experimental one. (author)