# Estimation of M1 scissors mode strength for deformed nuclei in the medium to heavy mass region by statistical Hauser-Feshbach model calculations

## TL;DR

This study investigates how the M1 scissors mode, dependent on nuclear deformation, improves the accuracy of neutron capture cross section predictions in medium to heavy deformed nuclei, with implications for nuclear astrophysics.

## Contribution

The paper introduces a deformation-dependent estimation of the M1 scissors mode strength in statistical Hauser-Feshbach calculations, enhancing the description of neutron capture data.

## Key findings

- Inclusion of the M1 scissors mode improves agreement with experimental data.
- The model better reproduces neutron capture cross sections for fission products and actinides.
- Potential impact on nucleosynthesis modeling of neutron-rich nuclei.

## Abstract

Radiative neutron capture is an important nuclear reaction whose accurate description is needed for many applications ranging from nuclear technology to nuclear astrophysics. The description of such a process relies on the Hauser-Feshbach theory which requires the nuclear optical potential, level density and $\gamma$-strength function as model inputs. It has recently been suggested that the M1 scissors mode may explain discrepancies between theoretical calculations and evaluated data. We explore statistical model calculations with the strength of the M1 scissors mode estimated to be dependent on the nuclear deformation of the compound system. We show that the form of the M1 scissors mode improves the theoretical description of evaluated data and the match to experiment in both the fission product and actinide regions. Since the scissors mode occurs in the range of a few keV $\sim$ a few MeV, it may also impact the neutron capture cross sections of neutron-rich nuclei that participate in the rapid neutron capture process of nucleosynthesis. We comment on the possible impact to nucleosynthesis by evaluating neutron capture rates for neutron-rich nuclei with the M1 scissors mode active.