Stopping power of Al, Cu, Ag, and Au for MeV hydrogen, helium, and lithium ions.Z13andZ14proportional deviations from the Bethe formula

Abstract

Stopping power of Al, Cu, Ag, and Au for 0.8-7.2-MeV/amu hydrogen, helium, and lithium ions has been measured by the calorimetric-compensation method to an accuracy of 0.5%. The data agree with most other published results and confirm the validity of earlier measurements by Andersen and co-workers. Higher-order $Z_1$ deviations from the Bethe formula have been examined. The experimental results agree with Lindhard's calculation of the $Z_1^3$ correction combined with a $Z_1^4$ term, which is slightly larger than Bloch's value. The experimental higher-order $Z_1$ contributions have a significant influence on the evaluation of empirical shell corrections, and the data are used to extract more realistic values. The deduced shell corrections show good agreement with Bonderup's calculations.