Limits on model-independent descriptions of elastic alpha-particle scattering

Abstract

Nearly unconstrained parametrizations of local optical-model potentials are used to investigate potential shapes which best reflect experimental data. The model dependence of optical-model analyses is investigated by removing as much of the parametrization bias as is practical, so that the analyses are mostly dependent on the sensitivity of the alpha-nucleus interaction and the precision of the experimental data. It is found that real- versus imaginary-potential correlations are the dominant limitation on model-independent analyses using local potentials; correlations decrease the effective sensitivity of the interaction to the interior of the real potential and are responsible for ambiguous solutions to the problem.NUCLEAR REACTIONS $\ensuremath{\alpha}$-nucleus optical potentials; model-independent parametrization. $^{50}\mathrm{Ti}(\ensuremath{\alpha}, \ensuremath{\alpha})$, ${E}_{\ensuremath{\alpha}}=140$ MeV.