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C. Lemell:
"Transport of highly charged ions through micro- and nanocapillaries";
Vortrag: Seminar Institut für Allgemeine Physik (IAP), TU Wien; 09.11.2004.

interaction of highly charged ions with solid surfaces a transient, highly excited state, the so-called "hollow" atom/ion is formed which quickly decays to the ground state of the projectile upon impact on the target surface. Only weak signatures of this process are experimentally accessible. Their interpretation is still under discussion.

One way to extract hollow atoms/ions to vacuum and investigate their properties directly is to transmit them through thin metal capillaries. A small fraction of projectiles entering the capillary will capture target electrons in close vicinity to the exit of the capillary without hitting the surface in a later stage of its
trajectory. Decay processes (radiative, Auger-type) can then be studied as a function of the distance from the capillary exit.

In a widely noticed follow-up experiment Stolterfoht et al. have shown that slow highly charged projectiles can be deflected by large angles if they are transmitted through capillaries manufactured into insulating materials. The initial charge state of the projectiles remains unchanged during the interaction. Deflection angles in this experiment reached up to 25 deg., opening a perspective to design ion-optical elements without electric supply.

In this talk I will give a short overview over available experimental data and the methods used in our group to model the transport of charged particles through capillaries. Good agreement with many experimental results could be achieved while other experimental features still remain unexplained.