Scaling and plasma diagnostic studies of Sr⁺ and Ca⁺ recombination lasers

Summary form only given. The authors report results of volume and repetition rate scaling experiments and plasma diagnostics with longitudinally excited (LE) Sr** plus and Ca** plus recombination lasers. In preliminary experiments investigating repetition rate scaling of large-volume tubes, mean powers exceeding 1 W on the lambda 430. 5-nm Sr** plus line and 0. 5 W on the lambda 373. 7-nm Ca** plus line for the 1000-cm**3 tube operating at only 500 Hz were observed. Corresponding energy conversion efficiencies were 0. 1 and 0. 5%, respectively. The problems of repetition rate scaling of these systems are discussed and results of current experiments aimed at extending the pulse rates into the kilohertz range are reported.