Extended analysis of the spectrum Si XI: compilation plus new measurements

The literature data on Si XI (Be-like ion) have been compiled with a critical re-analysis for their consistency. High-resolution EUV beam-foil spectra provided new data. With the help of Cowan code ab initio and parametric calculations and of isoelectronic comparisons a revised level scheme was constructed which includes most levels up to configurations with principal quantum number n = 5, as well as some n = 6 levels. About 200 spectral lines in the region 30-613 A are newly identified with transitions between configurations with n = 2, 3, 4, 5 and 6. (orig.)