Applicability of pre-equilibrium coalescence model to evaluation of alpha-particle production cross sections

Applicability of the pre-equilibrium coalescence model was investigated toward the construction of advanced and comprehensive nuclear data. This study was devoted to the analysis for nucleon- induced alpha-particle production cross sections up to 200 MeV. The optical model calculation was performed with suitable potential parameters both for incident- and outgoing- channels. The Iwamoto-Harada-Sato coalescence model was incorporated into the GNASH code in order to take account the pickup contribution from the pre-equilibrium stages. It was found that the present approach enabled us to reproduce measured cross sections better than empirical models which had been commonly used for nuclear data evaluations up to ~100 MeV. From comparisons between the model calculations and experimental data, we discuss the behaviors of the model parameters and applicability limit of the present approach.