Mechanism for Xe isotope production in the interaction of Ta nuclei with protons at Ep = 1 GeV

The cumulative yields, ranges, and F/B anisotropy of the angular distributions have been measured for the stable isotopes 124-132Xe, produced by bombarding Ta with 1-GeV protons. The correlation between the kinematic characteristics of the product nuclei and their nucleon composition is discussed. This correlation supports the idea that two basic mechanisms are operating in these reactions: spallation and fission. The ranges of the isotopes 130Xe and 132Xe are found to be significantly larger than those of the products of spallation reactions. On the other hand, they are much smaller than the characteristic ranges of fragments from the binary fission of target nuclei. It is concluded that refinements are necessary in the mechanism of an extremely asymmetric fission of Ta by protons with E = 1 GeV. The possibility of explaining the data on the basis of an admixture of a collective mechanism for proton-nucleus interactions is discussed. 19 refs., 4 figs., 2 tabs