X-ray observations of 2l-nl' transitions in Mo30+-Mo33+ from tokamak plasmas

X-ray spectra of 2p-nd transitions with 4≤n≤18 in molybdenum (Z=42) charge states around neonlike (Mo32+) have been observed from Alcator C-Mod plasmas. Accurate wavelengths (±0.1 m) have been determined by comparison with neighboring argon and chlorine lines with well-known wavelengths. Line identifications have been made by comparison to ab initio atomic-structure calculations, using a fully relativistic, parametric-potential code, and agreement between measured and theoretical wavelengths is good. Calculated wavelengths and oscillator strengths are presented for the strongest transitions with upper levels n between 4 and 14 to the lower levels n=2 in the four charge states Mo30+-Mo33+. Effects of configuration interaction have been observed in the intensities of lines with nearly degenerate energy levels.