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R. Bereczky, G. Kowarik, F. Aumayr, K. Tökési:
"Transmission of 4.5 keV Ar⁹+ ions through a single macroscopic glass-capillary";
Poster: 4th Conference on Elementary Processes in Atomic Systems (CEPAS), Cluj-Napoca/Romania; 18.06.2008; in: "4th Conference on Elementary Processes in Atomic Systems (CEPAS)", (2008), S. 105.

Investigations of the interactions of highly charged ions (HCI) with internal surfaces
recently became available due to the advances in the fabrication of nano-, micro-, and
macrocapillaries. The first measurements were performed using metallic microcapillaries
and the obtained experimental data were in good agreement with theoretical predictions.
Then investigations of HCIs and insulating nano-capillaries became available. In contrast
to the case of metallic capillaries guiding of the charged particles through nano-capillaries
tilted by large angles with respect to the direction of the incident beam was discovered
[ref ]. However, the slow HCI pro jectiles were not only able to simply pass through the
tilted capillaries, but they unexpectedly did so by keeping their initial charge state as a
consequence of a self-organized charge-up inside the capillary.
Since the experiments so far have used thin
Fig. 1. Angular distribution of 4.5 keV Ar9+
pro jectiles passing through a single glass macro-
capillary. The solid line is a Gaussian fit of the
measured data.
insulating foils with randomly distributed cap-
illaries (produced by swift heavy ion bombard-
ment) or ordered arrays of regular nano-capillaries,
collective effects due to the presence of neigh-
boring capillaries must be also taken into ac-
count for an accurate simulation of the ion tra jectories. These collective effects make
a full theoretical description of the interaction between charged particles and insulator
capillary walls rather difficult.
To obtain an easier situation for comparison with simulation, we have investigated
the transmission of 4.5 keV Ar9+ ions through a single, cylindrical-shaped glass capillary
of macroscopic dimensions (0.17 mm diameter and 11 mm length)produced in ATOMKI.
The measurements were carried out using HCI produced by the 14.5 GHz Electron Cy-
clotron Resonance ion source at Vienna University of Technology. The glass capillary
was positioned in an UHV chamber with a pressure of better than 10?8 mbar. The beam
was collimated by an aperture to a diameter of 3 mm and an opening angle of +/- 1.5?
and the transmitted pro jectiles were recorded by a position sensitive channelplate detec-
tor [ref. to HCI proc. J.Phys.Conf.Proc.] As a result we found that a electric guiding
field can also build-up inside such a macroscopic capillary and that slow HCIs can be
transmitted in wide range of the tilt angles (see Fig. 1.) in a similar manner than for
the case of nano-capillaries.
The work was supported by the "Stiftung Aktion ?Osterreich-Ungarn" grant no.
67?ou3, the Hungarian National Office for Research and Technology, the grant "Bolyai"
from the Hungarian Academy of Sciences, as well as Austrian FWF (P17449).

capillaries, highly charged ion, ion guiding