Energy loss of helium ions in zinc

Abstract

The energy loss of helium ions in zinc has been measured in the energy range from 37.5 to 1750 keV/ amu using the transmission technique and the Rutherford backscattering method. In addition, calculations using the extended Friedel sum rule, the unitary convolution approximation, and the local plasma approximation have been performed. The contributions of the inner-shell and valence electrons to the total energy loss are separately evaluated. The measurements and calculations are in good agreement over an extended range of energies, and both of them yield stopping values higher than those provided by SRIM 2003.

Experimental and theoretical study of the energy loss of C and O in Zn

“…It is worthwhile to mention that for ions heavier than Li, the experimental stopping power data are scarce except for some particular materials (C, Al, Si, Ag, Au) [3]. In zinc, no energy loss measurements for C and O ions have been reported in the literature.In previous papers, we have studied in a systematic way the stopping coefficients for a series of ions of increasing atomic numbers: H, He, Li, Be, and B in zinc [4][5][6][7][8], and with our theoretical formulation, we have been able to explain changes in the stopping power curves, reaching a very good agreement between the experimental and theoretical results. This agreement was achieved by a detailed theoretical study of the contribution of each individual charge state of the projectile and each electronic shell of the target.…”

“…The theoretical approaches used to calculate the energy loss of ions in solids have been described in detail in previous publications [6][7][8].…”

“…[17]. The stopping power due to valence electrons was calculated considering them as a free electron gas (FEG) using the TCS-EFSR approach [9], as described in previous papers [6][7][8]. The TCS-EFSR is a nonlinear or nonperturbative model, since it contains no linearizing or perturbative assumptions, and, therefore, it applies to all orders in the interaction.…”

The energy loss straggling of low Z ions in solids and gases

“…While employing the SLPA for the different moments of the energy loss, we have found that even in the case of He ions, ionization cross sections and stopping cross sections are very different for He 0 or He 2+ [51]. However, this is not the case for the energy loss straggling as observed in Figs.…”

“…The Levine-Louie dielectric function [47] keeps the virtues of Lindhard one [31]: electron-electron correlation to all orders, collective response, and fsum rule (particle number conservation). The SLPA with Levine-Louie dielectric function has been employed with good results in stopping power calculations [15,[51][52][53][54][55] in an extended energy range, and in inner-shell ionization cross sections of very heavy targets at high impact velocities [29].…”