Isotopic effects in spallation and fission reactions and mass-spectrometer investigation of them with 1-GeV protons

An in line mass spectrometer has been used to investigate the isotope dependences of the yields of the product nuclei in nuclear reactions induced by 1-GeV protons on targets of light nuclei, 12C(p,X)6-9Li, 13C(p,X)6-9Li, medium nuclei, 90Zr(p,X) 74-86Rb, 91Zr(p,X) 76-88Rb, 71-84Br, 94Zr(p,X) 76-90Rb, heavy nuclei, Ir(p,X) 76-92Rb, 80-94Sr, 118-133Cs, 42-48K, U(p,X) 79-97Rb, 121-146Cs, and also U(p,X) 81-94Rb at Ep = 0.75 GeV. The high-precision measurements of the relative yields of some product isotopes have been used in a systematic study of even-odd and shell effects in nuclear reactions induced by intermediate-energy protons. Existing reaction models have been used to calculate the yields of the product nuclei for a series of isotope targets. Aspects of the spallation and fission reaction mechanisms for reactions induced by intermediate-energy protons are discussed on the basis of an analysis and comparison of the calculated and experimental isotope distributions. 52 refs., 20 figs., 10 tabs