Precise charge state distribution of projectile ions through solid targets

TL;DR

This paper develops a multi-formula model to accurately predict the charge state distribution of projectile ions in solid targets within the intermediate energy range, improving upon previous empirical formulas and matching experimental data.

Contribution

The authors introduce a model using four formulae for better prediction of charge state distributions, extending accuracy to higher atomic numbers than prior empirical formulas.

Findings

The multi-formula model aligns well with experimental data across various ions.

Gaussian distribution with a specific width accurately describes the CSDs.

Improved prediction of charge states benefits ion-atom collision and accelerator physics.

Abstract

The charge state distribution (CSD) of the projectile ions through solid targets in the intermediate energy range (1 MeV/u $<$ E $<$ 4 MeV/u) has a major impact on the collision of the ion atom and accelerator physics. We explore the mean charge states taken from the empirical formula [Schiwietz $et~al.$, Nucl. Inst. Meths. {\bf 225}, 4(2004)] are only good for projectile ions with $Z_1 \le 16$. To solve this issue, we develop a model in which instead of a single formula, if we employ four formulae, the comparative picture between experimental and empirical data becomes impressive. Furthermore, the CSDs with the mean charge state so obtained and the Gaussian distribution function having distribution width given by [Novikov and Teplove, Phys. Lett. {\bf378}, 1286(2014)] compare well with the experimentally measured CSDs for the entire range of projectile ions. We believe that precise CSDs will be highly useful in both ion-atom collision and accelerator physics.