Charge-state evolution of highly charged ions transmitted through microcapillaries

The charge-state evolution of highly charged ions transmitted through microcapillaries is studied theoretically by a classical trajectory Monte Carlo simulation. The interaction of highly charged ions with the internal surface of the capillary is treated within the framework of dielectric response theory. We analyze the distance of closest approach and the angular distributions of the highly charged ions at the exit of the microcapillary. We find the charge-state fraction of transmitted N⁶⁺ projectiles, in good agreement with first measurements. Moreover, our calculations indicate that grazing collisions with the microcapillary surface hold the promise of direct observation of charge transfer and hollow-atom formation at a large distance from the surface.