Coupled-channels analysis of nucleon interaction data of ²⁸'³⁰Si up to 200 MeV based on the soft rotator model

A consistent analysis for nuclear level structure and nucleon scattering data up to 200 MeV was performed for sd-shell nuclei, ^28,30Si, using a unified framework of soft-rotator model and coupled-channels approach. The ^28,30Si were assumed to be deformed nuclei having oblate shapes. The soft-rotator model parameters were determined so as to reproduce measured collective levels of ^28,30Si up to an excitation energy of around 10 MeV. The relativistic kinematics and global optical potential form were taken into account in the coupled-channels optical model analysis, and the optical model parameters were derived. The calculation showed good agreement with experimental data for both collective levels and nucleon interaction data—neutron total cross sections, proton reaction cross sections, and nucleon scattering angular distributions.