Cross sections were measured for the production of radioactive isotopes by proton-induced reactions in natural aluminum, iron, and copper at bombarding energies of 60 MeV and lower. Most of the induced activities with half-lives of greater than 1 h were recorded. Cyclotron-accelerated protons were used to bombard stacked foils which were subsequently individually analyzed for their $\gamma$ radiation with a Ge(Li) spectrometer. Cross sections predicted from an evaporation theory and from cascade-evaporation theory were compared with experimental values; reasonable agreement was obtained.

• Received 15 May 1967

DOI:https://doi.org/10.1103/PhysRev.162.1055