RADIATIVE LIFETIME OF LiH $A^{1}\Sigma^{+}$

Abstract

We have measured the radiative lifetime of $^{7}LiH A^{1}\Sigma^{+}, \nu^{\prime} = 5$ in several rotational levels. The results are as follows: $\tau(\nu^{\prime} = 5, J^{\prime} = 5) = 32.6 \pm 4.2$ nsec, $\tau(\nu^{\prime} = 5, J^{\prime} = 10) = 32.6 ~\pm ~3.0$ nsec, and $\tau(\nu^{\prime} = 5, J^{\prime} = 15) = 29.0 ~ \pm~ 3.2$ nsec. These results are in excellent agreement with the experimental results of Dagdigian (this session) and the ab initio work of Docken and Hinze. The LiH is formed in a heat pipe oven, and total quenching rates by Li $(^{2}S)$ have been obtained. The results are as follows: $\sigma(v^{\prime} = 5 J^{\prime} = 5) = 350 \pm 50$ {\AA}$^{2}, \sigma(\nu^{\prime} = 5, J^{\prime} = 10) = 220 \pm 30$ {\AA}$^{2}$, and $\sigma(\nu^{\prime} = 5, J^{\prime} = 15) = 120 \pm 30$ {\AA}$^{2}$.