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Separation of Inner Shell Vacancy Transfer Mechanisms in Collisions of Slow Ar17+ Ions with SiO2
Published
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
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 Ar<sup>17+</sup> Ions with SiO<sub>2</sub>, Journal of Physics B-Atomic Molecular and Optical Physics
(Accessed October 1, 2025)