Bethe-Bloch Stopping Power Parameters for Al, Cu, and Ag Extracted from Recent Accurate Measurements

Accurate measurements of the stopping powers of Al, Cu, Ag, and Au for protons, ..cap alpha.. particles, and Li ions have been analyzed to extract values of mean excitation energy (I) and Barkas-effect parameter (b) for each target material. Two versions of shell corrections were employed, with only one yielding consistent, plausible results. Recommended values of I and b for Al, Cu, and Ag are, respectively, 165 +/- 3 eV and 1.37 +/- 0.05, 329 +/- 4 eV and 1.36 +/- 0.06, and 483 +/- 5 eV and 1.30 +/- 0.07.