Atomic Site-Sensitive Processes in Low Energy Ion-Dimer Collisions

作者：Iskandar W^*; Matsumoto J; Leredde A; Flechard X; Gervais B; Guillous S; Hennecart D; Mery A; Rangama J; Zhou C L; Shiromaru H; Cassimi A

来源：Physical Review Letters, 2014, 113(14): 143201.

DOI：10.1103/PhysRevLett.113.143201

Electron capture processes for low energy Ar9+ 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) over right arrow) where (b) over right arrow is the impact parameter vector in the molecular frame.

• 出版日期2014-10-2
• 单位中国地震局