Charge state dependence of L-shell X-ray production cross sections of 28Ni, 29Cu, 30Zn, 31Ga and 32Ge by 12 MeV 16Oq+ ions

Abstract

L-shell X-ray production cross sections of elements from Z2=28 to 32 were measured. A 12 MeV incident oxygen beam, with and without K-shell vacancies, was used to make a charge state dependence analysis. Simultaneous measurements were made of both scattered particles and X-rays from the ultra-clean foils that had been made sufficiently thin to reach the single-collision regime. Target L-shell to projectile K-shell electron capture for hydrogen-like (q=Z1−1) and fully stripped (q=Z1) oxygen ions were then extracted. The measurements are compared with the predictions of the ECPSSR theory using a single-hole fluorescence yield. In general and contrast to the first Born calculations, this theory gives reasonable agreement with the data for oxygen ions without K vacancies. However, the ECPSSR still significantly overpredicts the data for oxygen ions with K vacancies.