Separation of Inner Shell Vacancy Transfer Mechanisms in Collisions of Slow Ar17+ Ions with SiO2

Published

January 1, 2001

Author(s)

E Takacs, Z Ber nyi, John D. Gillaspy, L P. Ratliff, Ronaldo Minniti, J Pedulla, R Deslattes, N Stolterfoht

Abstract

We have studied the spectrum of x-rays emitted when hydrogen-like argon ions impact silicon dioxide surfaces. Specifically, we were interested in the mechanism for creation of K-shell holes in the silicon target atoms, which can be filled with the release of a 1.75 keV x-ray. Two mechanisms have been hypothesized for the vacancy transfer between the K shells of silicon and argon atoms: 'direct vacancy transfer' and 'projectile decay product mediated vacancy transfer'. To separate these mechanisms, we used a target with a metallic coating (preventing close collisions between Si and Ar but allowing x-ray transmission) and a target without such a coating. We found that x-ray photo-ionization is the dominant mechanism in both cases and measured an upper limit for the contribution from the direct mechanism' on the uncoated sample. Furthermore, we measured the relative strengths of the K α, K β, and K γ lines of the argon projectile as a function of kinetic energy and compared with charge exchange and cascade model calculations.

Citation

Journal of Physics B-Atomic Molecular and Optical Physics

Volume

34

Pub Type

Journals

Keywords

highly charged ions, surface interactions, vacancy transfer, x-ray spectroscopy

Citation

Takacs, E. , Ber nyi, Z. , Gillaspy, J. , Ratliff, L. , Minniti, R. , Pedulla, J. , Deslattes, R. and Stolterfoht, N. (2001), Separation of Inner Shell Vacancy Transfer Mechanisms in Collisions of Slow Ar¹⁷⁺ Ions with SiO₂, Journal of Physics B-Atomic Molecular and Optical Physics (Accessed December 10, 2024)