The elusiveness of multifragmentation footprints in 1-GeV proton-nucleus reations

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.