Necked-in Superdeformed Nuclei

Research output: ThesisDoctoral Thesis (compilation)

Abstract

Superdeformation, i.e. elongated shapes with the longest axis approximately twice as long as the shorter axes, has provided many new insights in nuclear structure. In this dissertation the possibility of forming superdeformed states related to two connected spheres, having a more or less pronounced neck, is investigated. Detailed Nilsson-Strutinsky calculations with the cranked Woods-Saxon potential and a finite-range liquid drop model are carried out in the 180Hg region, where superdeformed states related to two overlapping 90Zr are predicted. Detailed spectroscopic properties are calculated.

The effect of the necking degree of freedom on the the giant dipole resonance, GDR, is investigated. The calculations are carried out with the Woods-Saxon potential for the single-particle states, and the random phase approximation formalism for the phonon states. The residual interaction and coupling constants are determined by requirements of translational invariance. The lower energy component of the GDR spectrum for superdeformed shapes, corresponding to vibrations along the symmetry axis, is diminished with increasing necking, and the mean energy of the GDR is increased.

The folded Yukawa-plus-exponential liquid drop models take into account the finite range of the nuclear force, which is important when elongated and necked-in nuclear shapes are considered. However, it is shown that they are unstable towards higher multipole deformations, and that unphysical shapes are obtained in free minimizations when too high multipole deformations are included. Limits on multipolarity are given as functions of mass number.

Details

Authors
  • Lars-Ove Jönsson
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Sciences

Keywords

  • Matematisk och allmän teoretisk fysik, thermodynamics, statistical physics, gravitation, cranked Nilsson-Strutinsky, superdeformation, necked-in shapes, RPA, giant dipole resonance, finite-range liquid drop model, Mathematical and general theoretical physics, classical mechanics, relativity, quantum mechanics, klassisk mekanik, kvantmekanik, relativitet, statistisk fysik, termodynamik, Fysicumarkivet A:1997:Jönsson
Original languageEnglish
QualificationDoctor
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date1997 Apr 25
Publisher
  • Department of Mathematical Physics, Lund University
Print ISBNs91-628-2455-4
Publication statusPublished - 1997
Publication categoryResearch

Bibliographic note

Defence details Date: 1997-04-25 Time: 10:15 Place: Kårhusets hörsal, LTH External reviewer(s) Name: Ring, Peter Title: Professor Affiliation: Technische Universität München, Germany --- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Mathematical Physics (Faculty of Technology) (011040002)