RESUMO
Molecular and negative ion beams, usually produced in special ion sources, play an increasingly important role in fundamental and applied atomic physics. The ATOMKI-ECRIS is a standard ECR ion source, designed to provide highly charged ion (HCI) plasmas and beams. In the present work, H(-), O(-), OH(-), O(2)(-), C(-), C(60)(-) negative ions and H(2)(+), H(3)(+), OH(+), H(2)O(+), H(3)O(+), O(2)(+) positive molecular ions were generated in this HCI-ECRIS. Without any major modification in the source and without any commonly applied tricks (such as usage of cesium or magnetic filter), negative ion beams of several µA and positive molecular ion beams in the mA range were successfully obtained.
RESUMO
We report unprecedented transmission experiments of 3 keV Ne7+ ions through capillaries of 100 nm diameter and 10 microm length produced by etching ion tracks in a polymer foil. We studied foils tilted up to +/-20 degrees for which the incident ions are forced to interact with the capillary surface. Surprisingly, the majority of Ne7+ ions were found to survive the surface scattering events in their initial charge state. The angular distributions of the transmitted particles indicate propagation of the Ne7+ ions along the capillary axis. This capillary guiding of the Ne7+ ion provides evidence that the inner walls of the capillaries become charged and electron capture from the surface is suppressed in a self-organizing process.
RESUMO
Experimental evidence has been found for consecutive projectile-target-projectile (triple) and projectile-target-projectile-target (quadruple) "ping-pong" scattering of ionized target electrons in single C+ +Xe collisions at 150 and 233 keV/u impact energies. Distinct signatures of the multiple electron scattering contributions to the high-energy part (300-3400 eV) of the double differential electron spectra have been separated and identified with the help of reference measurements using He+ projectile ions and different calculations.
