Diagnostic of charge balance in high-temperature tungsten plasmas using LLNL EBIT.

ABSTRACT

Diagnostic of high-temperature M-shell W plasmas is challenging because of contribution of numerous ionization stages in a relatively narrow x-ray spectral region. A method using LLNL EBIT data generated at different electron beam energies has been established for the identification of prominent spectral features and for the determination of charge balance in x-ray M-shell W spectra between 3.5 and 8.5 A. It extends previous work [A. S. Safronova et al., Can. J. Phys. 86, 267 (2008)] which used only Ni-like lines to include the neighboring ionization stages. This diagnostic procedure was tested with results from Z-pinch plasmas produced on the 1 MA pulse power generator Zebra at UNR. These results are of particular importance for fusion research.