Journal of Gansu Lianhe University

Predissociation and collisional transfer on the high-lying on the Rb_2(~1Λ_g)

Dongdong Zhou

Published Jan 1, 2012• 0 citations

Abstract

Using a YAG-laser pumped OPO laser excite the pure rubidium cell,the Rb2(1Σg) state was excited to Rb2(1Λg) state,the temperature controlled between 519-548K while Rb atomic density ranged 4-8×1015cm-3 and Rb2 density was about 1014cm-3.The fluorescence spectrum of cesium vapor was used to study predissociation and transfer collision.From time-resolved fluorescence for the 1Λg →B1Πu transition at different Rb densities,the effective lifetimes of the 1Λg state could obtain.Based on the Stern-Volmer equation,the sum of the radiative and predissociative rates and the total cross section for deactivation of the Rb2(1Λg) were from the slope and the intercept,due to a linear relationship between the effective lifetime reciprocals and Rb densities.The time-integrated intensities of I3[Rb2(1Λg→B1Πu)],I2[Rb(8S→5P3/2)]and I1[Rb(6D→5P3/2)] were measured by photon counter.By combining the slope and the intercept with the result obtained by the Stern-Volmer equation,we obtain predissociative rates ΓP8S=(6.5±0.6)×106S-1,ΓP6D=(4.1±0.3)×106S-1,and collisional transfer cross sections σ8S=(7.9±0.7)×1013cm2,σ6D=(6.2±0.3)×10-13cm2.

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