Multicharged ion–surface measurements at ORNL MIRF using decelerated beams

Abstract

Studies are reported of low energy multicharged ion–surface interactions carried out at the ORNL MIRF (Multicharged Ion Research Facility) utilitizing recently developed apparatus that implements a UHV floating scattering chamber. By means of a zoom lens at the entrance to the chamber, beams can be decelerated to interaction energies as low as a few eV per charge. After a description of the new apparatus and of some diagnostic measurements of the decelerated beams, we present initial measurements of backscattered projectile energy loss and charge state distributions of multicharged carbon, oxygen, and argon ions incident on Au(1 1 0), with energies down to a few 100 eV/ q, and incident angles ranging from normal to 70 ∘ from normal. These results were obtained utilizing a TOF system with a biasable drift tube for charge state analysis.