“Plasma” effect in the formation of long lifetime Rydberg states Original Research Article

“Plasma” effect was clearly observed when photoemission electron beam was applied to excite atoms or molecule on the time-of-flight MS. The ion cloud was formed in the environment of high electron density. The ion cloud could trap low energy electron to form plasma. Villeneuve model was used to explain plasma effect. With plasma disappearing, the long lifetime Rydberg states were formed gradually. The three-body recombination mechanism of low energy electrons with ions was discussed.