title: Lifetime and yield of metastable Ar2(+) ions.
abstract: Ar2(+) ions produced in a cooled supersonic expansion by electron-impact ionization are accelerated at 2.5 keV and kept during few milliseconds inside a linear electrostatic trap. The lifetime of the metastable Ar2(+) ion is determined from the measurement of the rate of the argon atoms escaping the trap. The lifetime and the relative metastable populations are measured as a function of the pressure and temperature in the supersonic expansion, i.e., of the mean cluster size. Possible mechanisms responsible for the metastable formation are discussed.
authors.affiliation: Centre de Cinétique rapide ELYSE, Université Paris-Sud, Orsay Cedex, France.
authors.forename: V
authors.initials: V
authors.lastname: Lepère
authors.forename: I M
authors.initials: IM
authors.lastname: Ismail
authors.forename: M
authors.initials: M
authors.lastname: Barat
authors.forename: J A
authors.initials: JA
authors.lastname: Fayeton
authors.forename: Y J
authors.initials: YJ
authors.lastname: Picard
authors.forename: K
authors.initials: K
authors.lastname: Wohrer
authors.forename: C
authors.initials: C
authors.lastname: Jouvet
authors.forename: S
authors.initials: S
authors.lastname: Martrenchard