Desaktivierung angeregter He-Atome (31P1, 31S0, 41S0, 51S0, 61S0) durch Rb-Atome

Total collisional depopulation rates for He(n¹S₀) (3 ≦ n ≦ 6), He(3¹P¹) in thermal collisions with Rb have been measured using the transient-decay method. The measured quenching cross-sections increase from 4.3 · 10^?10 cm² to 24 · 10^?14 cm² with increasing n from 3 to 6. Comparison of experimental results with theoretical estimations shows that the main processes of quenching depend on n. He-atoms in the n = 3, 4 states are mainly quenched by Penning ionisation and higher excited states by collisional l-mixing.