# Experimental status of the nuclear spin scissors mode

## TL;DR

This paper investigates the nuclear spin scissors mode in actinides and rare earth nuclei using the Wigner Function Moments method, explaining experimental double hump structures and predicting different modes.

## Contribution

It provides a natural explanation for the double hump structure in $^{232}$Th and predicts the nature of the two peaks as different scissors modes.

## Key findings

- Double hump structure in $^{232}$Th explained by WFM
- Lower peak linked to isovector spin scissors mode
- Higher peak associated with orbital scissors mode

## Abstract

With the Wigner Function Moments (WFM) method the scissors mode of the actinides and rare earth nuclei are investigated. The unexplained experimental fact that in $^{232}$Th a double hump structure is found finds a natural explanation within WFM. It is predicted that the lower peak corresponds to an isovector spin scissors mode whereas the higher lying states corresponds to the conventional isovector orbital scissors mode. The experimental situation is scrutinized in this respect concerning practically all results of $M1$ excitations.