Abstract
The quest for the heaviest nuclei that can exist is a basic topic in natural science as their stability is characterized by a delicate interplay of short range nuclear forces acting between the nucleons (protons and neutrons) and long-range Coulomb forces acting solely between charged particles, i.e. the protons. As the stability of a nucleus is strongly correlated to its structure, understanding the nuclear structure of heaviest nuclei is presently a main challenge of experimental and theoretical investigations concerning the field of Superheavy Elements. At the velocity filter SHIP at GSI Darmstadt an extensive program on nuclear structure investigations has been started about a decade ago. The project covered both as well systematic investigations of single particle levels in odd-mass isotopes populated by α-decay as investigation of two- or fourquasi-particle states forming K isomers and was supplemented by direct mass measurements at SHIPTRAP and investigation of spontaneous fission properties. Recent experimental studies allowed to extend the systematics of low lying levels in N = 151 and N = 153 up to 255Rf and 259Sg, investigation of possible relations between nuclear structure and fission properties of odd-mass nuclei and investigation of shell strengths at N = 152 and towards N = 162.
Highlights
On the basis of the nuclear drop model, first suggested by C.F. von Weizsäcker in 1935 [1] instability of the atomic nucleus against prompt disruption was expected at Z 106, the exact value depending on the parametrization of the contributions, like volume energy, Coulomb energy etc
Extrapolations of the nuclear shell model performed in the midths of the sixties of the last century lead to the prediction of spherical proton and neutron shells at Z = 114 and N = 184 [2,3]
For about three decades predictions were based on macroscopic-microscopic models which agreed in the originally predicted spherical shell closures and, in advanced versions [4,5], predicted another island of enhanced stability in a region of strong prolate deformation around Z = 108 and N = 162
Summary
On the basis of the nuclear drop model, first suggested by C.F. von Weizsäcker in 1935 [1] instability of the atomic nucleus against prompt disruption was expected at Z 106, the exact value depending on the parametrization of the contributions, like volume energy, Coulomb energy etc. Extrapolations of the nuclear shell model performed in the midths of the sixties of the last century lead to the prediction of spherical proton and neutron shells at Z = 114 and N = 184 [2,3] Nuclei around these shell closures, soon denoted as ‘superheavy’, were expected to be stabilized against prompt fission by large ground state correction energies (‘shell effects’); long half-lives were expected. In the present paper we will discuss some aspects related to the properties of superheavy elements, systematics of low lying Nilsson levels in N = 151 and N = 153 even-Z isotones, possible relations between nuclear structure and fission hindrance in odd mass nuclei, and the trend of 2n – binding energies in N – Z = 50 even-even nuclei towards the predicted neutron shell at N = 162
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
