Charge-state measurements for 63Cu, 90Zr, 107Ag, 115In, 127I and 197Au in carbon for energies below 1 MeV/u

Abstract Equilibrium charge-state distributions have been measured for ∼0.2–1.0 MeV/u 63 Cu, 90 Zr, 107 Ag, 115 In, 127 I and 197 emerging from thin (10–30 μg/cm 2 ) carbon foils. In many cases, values deduced for the mean charge were found to deviate substantially (from 1 to 3 charge states) from those predicted by semi-empirical formulae. Highly asymmetric charge-state distributions were observed for 107 Ag and 115 In near 30 MeV, which are attributed to a shell effect at the boundary between the N- and M-shell electrons. The present results will be used to select the optimum charge-state combinations for heavy-ion beams from the tandem accelerator superconducting cyclotron (TASCC) at Chalk River.