Cross Sections for the Production of Cl, K, Ca, and Sc Isotopes in the Bombardment of Pb and U with 3.0-Bev Protons

Abstract

Cross sections for the formation of some nuclides in the mass number range 38-48 in the bombardment of Pb and U with 3.0-Bev protons have been measured. The maximum of the isobaric yield distributions for the nuclides from the Pb bombardment occurs at the stability line, while that from U is somewhat on the neutron-excess side. Total cross sections of 4-5 mb per mass number are deduced from the Pb data leading to a revision of the mass-yield curve in this region as proposed by Wolfgang et al. The cross sections from uranium are approximately twice as large as those from Pb. The data are shown to be consistent with a cascade-fission-evaporation mechanism.