摘要
The experiment was carried out using the Reaction Microscope mounted at the 320 kV platform for multidisciplinary research with highly charged ions at the Institute of Modern Physics,CAS[1,2].For reaction channel of(Ar2)^(2+)→Ar^(+)+Ar^(+),the kinetic energy release(KER)distribution clearly shows two peaks.The left peak locates at 3.7 eV approximately,and the right one lies at about 5.3 eV.From the classical reflection approximation KER/(Z1-Z2)=R,the internuclear distance R can be deduced.We find that the corresponding internuclear distance of the left peak is 3.8˚A,which is the equilibrium internuclear distance of the Ar2 dimer.This indicates that coulomb explosion takes place immediately after the double ionization process,without the involvement of the geometry change of the cluster ion.Therefore,the left peak dominantly arises from two-site double ionization.
基金
National Key R&D Program of China(2017YFA0402400,2017YFA0402300)
National Natural Science Foundation of China(11274317,U1532129)。