[Collisional transfer of the Cs(8S) state and excitation of high lying atomic states].
Xiu-Hua Cui, Baoxia Mu, Shuying Wang, Gang-Tai Zhang, Qianghua Yuan, Kang Dai, Yifan Shen
Abstract
Using selective stepwise excitation of the cesium 8S atomic level in Cs vapor, the collisional transfer and the population of the high-lying atomic states were studied in detail. At cesium densities of 10(16)-10(17) cm(-3), the rate coefficient of excitation collision [i. e., 8S+6S --> 6D+6S] was measured. Measurement of fluorescence intensities as a function of Cs density yields k6D = (2.4 +/- 0.5) x 10(-10) cm3 x s(-1). The 5D state was populated by the 8S --> 7P --> 5D transitions. The energy pooling collisions 5D+5D --> nL+6S (nL = 9D, 11S, 7F) were also studied. The rate coefficients were measured relative to the known rate coefficient of the collision [i. e. 6P+5D --> 6S+7D]. The densities of 6P state were combined with measured fluorescence ratios to determine rate coefficients for EP process. The average values (in unites of 10(-10) cm3 x s(-1)) for nL = 9D, 11S and 7F are 6.4 +/- 3.2, 1.0 +/- 0.5 and 8.4 +/- 4.2, respectively.