Date: November 1986
Creator: Lapicki, Gregory; Mehta, R.; Duggan, Jerome L.; Kocur, P. M.; Price, J. L. & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Description: This article discusses multiple outer-shell ionization effect in inner-shell x-ray production by light ions. Abstract: L-shell x-ray production cross sections by 0.25-2.5-MeV ₂⁴He+ ions in 28Ni, 29Cu, 32Ge, 33As, 37Rb, 38Sr, 39Y, 40Zr, and 46Pd are reported. The data are compared to the first-Born approximation and the ECPSSR theory that accounts for the projectile energy loss (E) and Coulomb deflection (C) as well as the perturbed-stationary-state (PSS) and relativistic (R) effects in the treatment of the target L-shell electron. Surprisingly, the first Born approximation appears to converge to the data while the ECPSSR predictions underestimate them in the low-velocity limit. This is explained as the result of improper use of single-hole fluorescence yields. A heuristic formula is proposed to account for multiple ionizations in terms of a classical probability for these phenomena and, after it is applied, the ECPSSR theory of L-shell ionization is found to be in good agreement with the data.
Contributing Partner: UNT College of Arts and Sciences