Nuclear Reactions of Ti,Fe,Co,Ni,Cu,and Zn by 500-MeV Protons

Formation cross sections of product nuclides in the nuclear reactions of Ti, Fe, Co, Ni, Cu, and Zn targets by 500-MeV protons were measured with a Ge(Li) γ-ray spectrometer. The measured cross sections in the mass range between \(A\cong40\) and \(A\cong{A}_{\text{T}}-4\) were used in the charge-dispersion analysis, where A T is the mass number of the target nucleus. The N / Z ratio of the charge-dispersion peak was found to be consistent with those obtained in the same mass range of spallation products in the nuclear reactions of the same medium-mass targets with 12-GeV protons. The mass-yield curve falls sharply with decreasing masses of product nuclides in contrast to relatively flat distributions at higher energies.