与铷(5~2S_(1/2))原子碰撞产生的铷7~2D态精细结构转移截面

Fine-structure transition cross-sections in 7~2D states of Rb induced in collisions with 5 ~2S_(1/2) state atoms

本文报道使用蒸汽泡和两光子两步激发方法,测量原子激发态敏化荧光I_(3/2)~1和直接荧光I_(3/2)~2其与温度的关系,得到与基态(5~2S_(1/2)铷原子碰撞产生的铷7~2D_(5/2)→7~2D_(3/2)和7~2D_(3/2)→7~2D_(5/2)精细结构转移截面分别为:σ_(fs)=4.7×10^(-13)cm^2、σ_(fs)~’=7.0×10^(-13)cm^2;碰撞转移出7~2D双态的转移截面σ_(tr)(5/2)=0.62×10^(-13)cm^2.由计算的7~2D态几何截面σ_(geom)能够相对很好地描述σ_(fs)和σ_(fs)~’的数量级.

In a vapor cell, the relative intensities of a sensitized fluorescence I3/21 and a direct fluorescence I3/22, as a function of T (100 to 200℃), had been measured by the methods of selective stepwise excitations with a Rb lamp and a tunable CW dye laser. From these measurements, the fine-structure transition cross-section in the 7 2D states of Rb induced in collidsion with ground-state Rb atoms were determined to be σfs (7 2D5/2→72D3/2) = 4.7 × 10-13 cm2 and σfs1 (7 2D3/2→7 2D5/2) = 7.0 × 10-13cm2 and the cross-section for transfer of excited Rb 7 2D-state atoms out of the doublet were also determined as σtr(5/2) (7 2D5/2→states other than Rb 7 2D) = 0.62 × 10-13 cm2. The calculcted result for the geometrical cross-section of excited Rb 7 2D state shows that the magnitunes of σfs and σfs1 can be described relatively well by σgeom.