  Electron capture processes for low energy Ar9+ ions colliding on Ar2 dimer
targets are investigated, focusing attention on charge sharing as a function of
molecule orientation and impact parameter. A preference in charge-asymmetric
dissociation channels is observed, with a strong correlation between the
projectile scattering angle and the molecular ion orientation. The measurements
provide here clear evidences that projectiles distinguish each atom in the
target and, that electron capture from near-site atom is favored. Monte Carlo
calculations based on the classical over-the-barrier model, with dimer targets
represented as two independent atoms, are compared to the data. They give a new
insight into the dynamics of the collision by providing, for the di erent
electron capture channels, the two-dimensional probability maps p(~b), where ~b
is the impact parameter vector in the molecular frame.
