研究了Cs(6P)+Cs(6S)+He→Cs(5D)+Cs(6S)+He的碰撞能量转移过程。单模半导体激光器共振激发Cs原子至6P_3／2态，利用另一与泵浦激光束反向平行激光束作为吸收线探测6P_3／2态原子密度及其空间分布。缓冲气体增大了6P_3／2和6S_1／2原子间的能量转移，这可从测量由Cs(6P)／Cs(5D)碰撞而被布居的7D态所发射的荧光得到证实。因5D→6P(3．0～3．6μm)处于红外本实验不能探测，利用一个已经测量过的过程(即6P+5D→6S+7D)作相对测量。得到三体碰撞速率系数为(2．2±1．1)×10^－28cm⁶S^－1。

An experimental study of energy transfer collisions,Cs(6P)+Cs(6S)+He→Cs(5D)+Cs(6S)+He,at thermal energies,was carried out in a cell. Atoms were excited to the 6P_3/2 state using a single-mode diode laser. The Cs(6P)atom density and spatial distribution were mapped by monitoring the absorption of a counter-propagating laser beam. The buffer gas enhanced the energy transfer between Cs(6P)and Cs(6S),which was based on the measurement of the fluorescence from the 7D state populated by the Cs(6P)/Cs(5D)collisions. Since the 5D→6P fluorescence(3.0～3.6μm)can not be detected with this experiment,the rate coefficient has been measured relative to the known rate coefficient of the collision(i.e.,6P+5D→6S+7D). The three-body collision rate coefficient [k3 =(2.2±1.1)×10^－28cm⁶s^－1]is obtained.