Lifetime and yield of metastable Ar2(+) ions.
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.
Lepère
V
V
Centre de Cinétique rapide ELYSE, Université Paris-Sud, Orsay Cedex, France.
Ismail
I M
IM
Barat
M
M
Fayeton
J A
JA
Picard
Y J
YJ
Wohrer
K
K
Jouvet
C
C
Martrenchard
S
S