COLLISIONAL-RADIATIVE MODELING OF THE L-SHELL EMISSION OF MO30-TEMPERATURE LOW-DENSITY TOKAMAK PLASMA( TO MO33+ EMITTED FROM A HIGH)

The x-ray spectra of several highly stripped molybdenum ions have been recorded between 0.6 and 5.5 Angstrom in the Frascati tokamak upgrade with a rotating crystal spectrometer. Detailed, quasi-steady-state co llisional-radiative models have been used to interpret emission featur es from inner shell, electron impact excitations in molybdenum ions ne ar the neonlike charge state and to characterize the charge state dist ribution in the plasma. Processes such as resonant excitation, excitat ion autoionization, and dielectronic recombination have been included in the models of the molybdenum ions' emission features. Introducing t he excitation-autoionization process into ionization equilibrium calcu lations brings agreement between observations and calculations of the relative ionization equilibrium fractions of highly stripped molybdenu m ions. Absolutely calibrated spectra and detailed models for the exci tation processes in these molybdenum ions allow us to calculate crucia l plasma parameters, such as the concentration of impurity ions in the plasma and the amount of power lost from the plasma through impurity line radiation.