Nuclear deformations in the region of the A=160 r-process abundance peak

TL;DR

This paper explores the deformation characteristics of neutron-rich rare-earth nuclei around A=160, linking nuclear structure to the observed abundance peak in the r-process, and discusses future experimental prospects.

Contribution

It provides new insights into nuclear deformation effects near A=160 and discusses the evolution of collectivity in neutron-rich isotopes using the Variable Moment of Inertia model.

Findings

Identification of deformation maxima in neutron-rich rare-earth nuclei.

Analysis of collectivity evolution with neutron number.

Discussion of experimental advancements for studying neutron-rich nuclei.

Abstract

In the abundance spectrum of r-process nuclei the most prominent features are the peaks that form when the r-process flow passes through the closed neutron shells. However, there are also other features in the abundance spectrum that can not be explained by shell effects, like the peak in the region of the rare-earth nuclei around mass A=160. It has been argued that this peak is related to the deformation maximum of the neutron-rich isotopes. Recently, both experimental and theoretical work has been carried out to study the deformation of neutron-rich rare-earth nuclei and to search for the point of maximum deformation. This work has focused on the nuclei around 170Dy in order to understand the evolution of collectivity in the neutron shell with 82 < N < 126. These investigations will be discussed in terms of the Harris parameters of the Variable Moment of Inertia model. Finally, we will discuss the future possibilities to reach further into the neutron-rich rare-earth region at the new experimental facilities using radioactive beams.