Radial profiles of impurity ions of carbon, neon and iron were measured for hightemperatureplasmas in large helical device (LHD) using a space-resolved extreme ultraviolet(EUV) spectrometer in the wavelength range of 60 A to 400 A. The radial positions of the impurityions obtained are compared with the local ionization energies, E_1 of these impurity ions and theelectron temperatures T_(ez) there. The impurity ions with 0.3 keV ≤ E_i≤ 1.0 keV are alwayslocated in outer region of plasma, i.e., 0.7≤ p≤ 1.0, and those with E_i <0.3 keV are located inthe ergodic layer, i.e., 1.0 ≤ p ≤ 1.1, with a sharp peak edge, where p is the normalized radialposition. It is newly found that T_(ez) is approximately equal to E_i for the impurity ions withE_i≤ 0.3 keV, whereas roughly half the value of E_i for the impurity ions with 0.3 keV ≤ E_i ≤1.0 keV. It is known that T_(ez) is considerably lower than E_i in the plasma edge and approachesto E_i in the plasma core. Therefore, this result seems to originate from the difference in thetransverse transport between the plasma edge at p ≤1.0 and the ergodic layer at p ≥ 1.0. Thetransverse transport is studied with an impurity transport simulation code. The result revealedthat the difference appearing in the impurity radial positions can be qualitatively explained bythe different values of diffusion coefficient, e.g., D = 0.2 m^2/s and 1.0 m^2/s, which can be takenas a typical index of the transverse transport.
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