title: Atomic site-sensitive processes in low energy ion-dimer collisions.
abstract: Electron capture processes for low energy Ar(9+) ions colliding with Ar(2) dimer targets are investigated, focusing attention on charge sharing between the two Ar atoms as a function of the molecular orientation and the impact parameter. A preference for charge-asymmetric dissociation channels is observed, with a strong correlation between the projectile scattering angle and the molecular ion orientation. The measurements here provide clear evidence that projectiles distinguish each atom in the target and that electron capture from near-site atoms 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 new insight into the dynamics of the collision by providing, for the different electron capture channels, the two-dimensional probability maps p(b), where b is the impact parameter vector in the molecular frame.
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: W
authors.initials: W
authors.lastname: Iskandar
authors.affiliation: Department of Chemistry, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Matsumoto
authors.affiliation: Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: A
authors.initials: A
authors.lastname: Leredde
authors.affiliation: LPC Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, 14050 Caen Cedex 04, France.
authors.forename: X
authors.initials: X
authors.lastname: Fléchard
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: B
authors.initials: B
authors.lastname: Gervais
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: S
authors.initials: S
authors.lastname: Guillous
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: D
authors.initials: D
authors.lastname: Hennecart
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: A
authors.initials: A
authors.lastname: Méry
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: J
authors.initials: J
authors.lastname: Rangama
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: C L
authors.initials: CL
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shiromaru
authors.affiliation: CIMAP, CEA-CNRS-ENSICAEN, BP 5133, F-14070 Caen Cedex 5, France.
authors.forename: A
authors.initials: A
authors.lastname: Cassimi