Identical Bands Around the Isobaric Rare Earth Even-Even Nuclei with the Mass Number A = 164

TL;DR

This paper investigates identical bands in rare earth nuclei around A=164 using a new collective rotational formula and the interacting boson model, achieving excellent agreement with experimental data and providing insights into nuclear deformation and moments of inertia.

Contribution

It introduces a three-parameter collective rotational formula (CRF3) and applies the sd-version of the interacting boson model to describe identical bands and nuclear shapes in A=164 nuclei, enhancing theoretical understanding.

Findings

CRF3 accurately reproduces excitation energies.

Systematic analysis of moments of inertia shows gradual increase.

IBM potential energy surfaces reveal nuclear deformation.

Abstract

Eight pairs of rare earth normally deformed nuclei around the isobaric nuclei with A = 164 and have identical values of F-spin have been studied. These pairs of identical bands cover 16 mass units and are classified. We suggested a theoretical collective rotational formula containing three parameters (CRF3) as an extended version of Bohr-Mottelson model to calculate the ground state positive parity excitation energies. Also, the sd-version of the interacting boson model (IBM) has been used to describe the nuclear shapes by using the intrinsic coherent-state. The optimized models parameters for each nucleus are adjusted by using a simulation search program to minimize the root mean square deviation between the theoretical calculation and experimental excitation energies. The best adopted model parameters of the CRF3 are used to calculate the rotational frequencies, the kinematic and dynamic moments of inertia and the evolution of with increasing hw are systematically analyzed. A smooth gradual increase in both moments of inertia was seen. The calculated results agree excellently with the experimental ones which give strong support to the suggested CRF3. The adopted IBM parameters are used to calculate the potential energy surfaces which describe the nuclear deformation. The correlation quantities which identify the IB are extracted, exhibit identical excitation energies and energy ratios in their ground state rotational bands.