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

Published

January 1, 2001

Author(s)

Z Berenyi, N Stolterfoht, E Takacs, J Pedulla, R Deslattes, J Gillaspy, R Minniti, L Ratliff

Abstract

We have studied the spectrum of x-rays emitted when 130 and 200 keV kinetic energy 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 photoionization 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 Kα, Kβ and Kγ lines of the argon projectile as a function of kinetic energy and found satisfactory agreement with charge exchange and cascade model calculations.

Citation

Journal of Physics B-Atomic Molecular and Optical Physics

Volume

34

Issue

7

Pub Type

Journals

Keywords

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

Citation

Berenyi, Z. , Stolterfoht, N. , Takacs, E. , Pedulla, J. , Deslattes, R. , Gillaspy, J. , Minniti, R. and Ratliff, L. (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 September 7, 2024)