Collision dynamics of the Kr8+ + N2 system studied by a multi-coincidence technique

Abstract

We have developed a multi-coincidence technique to study MCI–molecule collisions. Using this technique, complicated reaction processes and collision dynamics in Kr8+ + N2 collisions have been successfully revealed in the energy region below 200 eV/u. The reaction processes in the single-, double-, triple- and quadruple-charge changing collisions are resolved and three low-energy collision phenomena, ‘peak-shifting’ of molecular ions, ‘peak-splitting’ and ‘anisotropic fragmentation’ of fragment ion pairs, are found in the time-of-flight spectra of target ions. By careful analysis of kinematics of all the products, it is concluded that the charge transfer in the Kr8+ + N2 collisions is dominated by multi-electron capture processes followed by electron emission and the collision dynamics is characterized by the transverse momentum transfer from the ion to the molecule and the appearance of the ‘anisotropic fragmentation’.