Energy Dependence of Product Yields in Copper Spallation by Protons between 3 and 30 GeV

Careful comparisons of cross sections for formation of 19 products of copper spallation by 3- and 30-GeV protons indicate only a small energy dependence in this energy range. As the energy is increased from 3 to 30 GeV, products of $A>40$ decrease in yield by 15% or less, except for some highly neutron-deficient species, while low-mass products increase in yield by 10 to 50%. These findings are somewhat at variance with earlier reports from CERN.