Spatial characterization of a divertor in the presence of an X-point MARFE by collisional-radiative modeling and line profile calculations

Koubiti, M.*; Nakano, Tomohide; Marandet, Y.*; Mekkaoui, A.*; Mouret, L.*; Rosato, J.*; Stamm, R.*

We have measured a profile of C IV spectral line emitted from the detached diverter plasma of JT-60U with a high-wavelength resolution spectrometer, and analyzed it with PPP code. In the previous analysis, the measured spectral profile was compared with the spectral profile calculated by the PPP code with one pair of electron density and temperature. With this method, the spectral profiles measured around the X-point were well reproduced, but the spectral profile measured at a very center of the X-point was not reproduced. In the present analysis, we have succeeded to reproduce the spectral profile measured at the very center of the X-point by synthesizing two spectra calculated with two pairs of electron densities and temperatures. One pair was 110 m and 23.0 eV, and the other 110 m and 2.5 eV. The contribution to the intensity of C IV spectral line of the first pair was 65% and that of the second 35%.