Iron forbidden lines in tokamak discharges

Abstract

Several spectrum lines from forbidden transitions in the ground configurations of highly ionized atoms have been observed in the discharges of Princeton Large Torus tokamak. Such lines allow localized observations, in the high-temperature regions of the plasma, of ion-temperatures, plasma motions, and spatial distributions of ions. Measured absolute intensities of the forbidden lines have been compared with simultaneous observations of the ion resonance lines. Model calculations have been carried out in order to deduce the relative importance of electron collisions and radiative decays in establishing excited-state populations.