计算和测量了Rb+(Ar,N2)混合蒸气中Rb(5P3/2)共振能级的有效辐射率。使用单模半导体激光器(抽运激光)将Rb原子激发至5P3/2态,另一调谐到5P3/2→7S1/2的单模激光束(检测激光)与抽运光束反平行通过样品池,并在池的径向平行移动,通过检测激光束的吸收测定了激发态原子密度及其空间分布。由于辐射陷获存在,有效辐射率为自然辐射率与透射因子(发射的光子在探测区域内没有被吸收的平均概率)的乘积。5P3/2原子密度及其空间分布结合5P3/2←5S1/2跃迁线的碰撞增宽计算了透射因子,从而得到了不同Ar或N2气压下,Rb D2线的有效辐射率。对5P3/2-Ar系统,在不同气压下测得的D2线强度比值与有效辐射率计算值的比值相符。对于5P3/2-N2系统,研究了电子态向振动态的碰撞转移,得到了转移截面。

The effective radiative rates for Rb (5P3/2) resonance level in the presence of Ar or N2 have been determined. Rb atoms were excited to the 5P3/2 state using a single-mode diode laser(pumping laser). The single-mode laser beam (probing laser) tuned to the 5P3/2→7S1/2 transition passes through samples paralled to the pumping laser. The excited-atom density and spatial distribution were mapped by monitoring the absorption of a counter propagating single-mode diode laser beam (probing laser). In the presence of radiation trapping, the effective radiative rate is the product of spontaneous radiation rate and transmission factor, which describes the average probability that photons emitted within the fluorescence detection region can pass through the optically thick vapor without being absorbed. The transmission factor is calculated by combining the 5P3/2 atom density and its spatial distribution and collisional broadening of 5P3/2←5S1/2 transition line. The effective radiative rates of the Rb D2 line as a function of the Ar or N2 pressure P are obtained. The fluorescence intensity I780 of the 5P3/2→5S1/2 emission is measured simultaneously. For 5P3/2-Ar system the measured fluorescence ratios determine the ratios of the effective radiative rates at different Ar densities. These ratios are in agreement with theoretical evaluation. For 5P3/2-N2 system the electronic to vibrational energy transfer has been investigated. The cross section was obtained.