One-nucleon pickup reactions and compound-nuclear decays

Abstract

One-nucleon transfer reactions, long used as a tool to study the structure of nuclei, are potentially valuable for determining reaction cross sections indirectly. This is significant, as many reactions of interest to astrophysics and other applications involve short-lived isotopes and cannot be measured directly. We describe a procedure for obtaining constraints for calculations of neutron capture cross sections using observables from experiments with transfer reactions. As a first step toward demonstrating the method, we outline the theory developments used to properly describe the production of the compound nucleus ⁸⁸Y^* via the one-nucleon pickup reaction ⁸⁹Y(p,d)⁸⁸Y^* and test the description with data from a recent experiment. We indicate how this development can be used to extract the unknown ⁸⁷Y(n,γ) cross section from ⁸⁹Y(p,dγ) data. The example illustrates a more generally applicable method for determining unknown cross sections via a combination of theory and transfer (or inelastic scattering) experiments.