Influence of theZ13contribution to stopping power on the evaluation of mean excitation potentials and shell corrections

The careful experimental evaluations of mean excitation potentials and of shell corrections need to be reexamined in view of the recent theoretical evaluation of the $Z_1^3$ contribution to the stopping power of matter for charged particles. We present here stopping power formulas including the $Z_1^3$ contribution and apply these to recalculate the excitation potentials and shell corrections derived from very precise measurements of stopping power for some elements in $20\le Z_2\le 30$. Including the $Z_1^3$ contribution does not appear to produce a significant change (considering current experimental accuracy) in the mean excitation potentials for elements in this range, but important changes are found in both the shape and magnitude of the shell-correction curves.