Charge-state distributions of relativistic gold-ion beams stripped by foils

Abstract

The dynamics of charge-state fractions of relativistic gold-ion beams stripped by foils from Be to Au is investigated in the 100 MeV/u to 10 GeV/u energy range. Calculations of the fractions as a function of foil thickness are performed using the recently developed breit code based on the analytical solution of the balance rate equations for the ion charge-state fractions. Relativistic electron-loss and electron-capture cross sections, required for breit as input data, are calculated. The influence of the beam energy loss on the charge-state fractions is found to be small: less than 15%. Calculated charge-state distributions are compared with available experimental data, obtained at the GSI (Gesellschaft f\ur Schwerionenforschung), RHIC (Relativistic Heavy Ion Collider), and BEVALAC (Bevatron Linear Accelerator) facilities, and calculations of the global code created at GSI. The present calculations of the charge-state distributions allow one to find the optimal conditions for the maximal yield of H-like, He-like, and bare gold ions at energies considered.