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We use the tools of hybrid intranuclear-cascade/nuclear-de-excitation models to evaluate the sensitivity of several physical observables to the inclusion of a multifragmentation stage in the deexcitation chain and assess the need for a multifragmentation model in the quantitative description of p + 56 Fe and p + 136 Xe reactions at 1-GeV incident energy. We seek clear signatures of multifragmentation by comparing different state-of-the-art de-excitation models coupled with intranuclear-cascade models and by focusing on discriminating observables such as correlations and fragment longitudinal-velocity distributions. None of the considered observables can be unambiguously interpreted as a multifragmentation footprint. The experimental data are best described as originating from sequential binary decays. However, no de-excitation model can reproduce the experimental longitudinal-volocity distributions from 1-GeV p + 136 Xe.

We measured integral thin target cross sections for the proton-induced production of He-, Ne-, and Ar- isotopes from Fe and Ni and of He-, Ne-, Ar-, Kr-, and Xe-isotopes from Bi from the respective reaction thresholds up to 2.6GeV. Iron and Ni are important structural materials for the planned ADS/EA systems and Bi is a major constituent for planned spallation neutron sources. In addition, we give new data for the production of 3 He from Mg, Al, Si, and Pb by revising earlier data and considering now 3 Hd iffusive losses and new information for the 3 H/ 3 He branching ratios. The data are compared to results from theoretical nuclear model codes.