# Predicting the optical observables for nucleon scattering on even-even actinides

## TL;DR

This paper extends a dispersive coupled-channel optical model to predict nucleon scattering on even-even actinides, incorporating a soft-rotator model for nuclear structure and achieving good agreement with experimental data.

## Contribution

The work introduces a novel extension of the optical model using SRM nuclear wave functions and volume conservation, improving predictions for actinide scattering.

## Key findings

- Accurate description of scarce experimental data
- Good agreement with global mass model parameters
- Significant differences in compound-nucleus formation cross sections

## Abstract

Previously derived Lane consistent dispersive coupled-channel optical model for nucleon scattering on $^{232}$Th and $^{238}$U nuclei is extended to describe scattering on even-even actinides with $Z=$90--98. A soft-rotator-model (SRM) description of the low-lying nuclear structure is used, where SRM Hamiltonian parameters are adjusted to the observed collective levels of the target nucleus. SRM nuclear wave functions (mixed in $K$ quantum number) have been used to calculate coupling matrix elements of the generalized optical model. The "effective" deformations that define inter-band couplings are derived from SRM Hamiltonian parameters. Conservation of nuclear volume is enforced by introducing a dynamic monopolar term to the deformed potential leading to additional couplings between rotational bands. Fitted static deformation parameters are in very good agreement with those derived by Wang and collaborators using the Weizs\"acker-Skyrme global mass model (WS4), allowing to use the latter to predict cross section for nuclei without experimental data. A good description of scarce "optical" experimental database is achieved. SRM couplings and volume conservation allow a precise calculation of the compound-nucleus formation cross sections, which is significantly different from the one calculated with rigid-rotor potentials coupling the ground-state rotational band. Derived parameters can be used to describe both neutron and proton induced reactions.