Rb(5PJ)+(Ne、N2)碰撞能量转移

在气体样品池条件下,研究了Rb(5PJ) (Ne、N2)碰撞能量转移过程.对于5PJ与Ne的碰撞,电子态能量仅能转移为Ne原子的平动能.在与N2的碰撞中,向分子振转态的转移是重要的.调频半导体激光器稍微调离共振线,激发Rb原子至Rb(5P3/2)态,在不同的Ne或N2气压下,测量了5P1/2→5S1/2与5P3/2→5S1/2荧光强度比.利用速率方程分析,可以得到碰撞转移速率系数,对于Ne,5P3/2→5P1/2转移速率系数为1.53×10-12cm3s-1.对于N2,由5PJ Ne和5PJ N2二种情况下5P1/2与5P3/2荧光的相对强度比,利用最小二乘法确定5P3/2→5P1/2.转移速率系数为8.83×1011cm3s-1,5PJ态猝灭速率系数为1.25×10-10cm3s-1.对实验结果进行了定性的讨论.

Rb(5PJ)+(Ne, N2) collisional energy transfer

The collisional energy transfer in Rb(5PJ)+M collisions,where M=Ne,N2 under gas cell conditions was investigated. For collision with Ne only electronic to translational energy transfer is possible. However,in the N2 case,electronics to vibrational or rotational transfer is important. The Rb(5P3/2)state is excited by a tunable CW diode laser,where the laser is tuned slightly off resonance. The ratio of 5P1/2→5S1/2to the 5P3/2→5S1/2 fluorescence as a function of quenching gas pressure was measured. Using a two-state rate equation model the transfer rate coefficients from the Rb(5PJ)state was obtained. The rate coefficient for 5P3/2→5P1/2 transfer in collision with Ne is 1.53×10－12cm3S－1. Using the ratio of the 5P1/2 to 5P3/2 fluorescence for Ne and N2 case,and fitting the experimental results to the rate equation analysis,we estimate that the rate coefficient for 5P3/2→5P1/2 transfer in collision with N2 is 8.83×10－11 cm3s－1. The quenching rate coefficient of the 5PJ state is 1.25×10－10 cm3s－1. A qualitative explanation for the results was given.