Ternary clusterization and quadrupole deformation

Abstract

The deformation-dependence of ternary clusterization of atomic nuclei is investigated. In particular, allowed and forbidden ternary clusterconfigurations are determined for the ground, superdeformed, and hyperdeformed states of some light and heavy nuclei, based on a microscopic (real and effective SU(3)) selection rule. The energetic stability of the clusterizations is also considered. The investigation of exotic nuclear shapes, e.g. superdeformed and hyperdeformed states is one of the most interesting topics in recent nuclear structure studies. The appearance of exotic cluster configurations (or exotic cluster decay) is another issue of utmost interest. The combination of these two problems brings us to an exciting question: what is the interrelation of these two phenomena, i.e. what are the possible clusterizations of nuclear states with exotic shapes. In the present Letter we address this question from the angle of the ternary clusterization. We apply methods which can be generalized to more complicated multicluster-configurations in a straightforward way.The basic concept of this work is that when we try to describe the composition of an atomic nucleus from smaller nuclei (clusters) then we take into account both of the two complementary natural laws, which govern this kind of phenomenon: the energy-minimum principle and the Pauli-exclusion principle. The crucial role of these two rules are obvious: energetically unfavored systems are not likely to appear, and when the building blocks are fermions, like the nucleons of the atomic nuclei, then they follow the exclusion principle. However, the exact role, or * Corresponding author.E-mail address: algora@atomki.hu (A. Algora).relative importance of these two aspects of clusterization among different circumstances are not completely understood yet; the present work is meant to be a contribution to this task. Much attention has been paid to the energetic preference of various cluster-configurations of a nucleus. The methods applied along this line are partly or completely empirical ones, using information gained from the experimental data. Furthermore, most of these works concentrate on the simplest, i.e. binary clusterizations, especially, when the energetic calculation involves (in addition to the experimental binding energies) intercluster potentials, like in the dinuclear system model [1], or in the local potential approach [2]. On the other hand the treatment of the exclusion-principle has to be done microscopically, therefore, apart from the light, or simplest heavy nuclei, it gives rise to large computational difficulties. Due to this fact no systematic studies has been done, and many of the experimentally interesting systems are untouched from this viewpoint.The main point of this Letter is to present a method for the approximative treatment of the exclusion principle, which can be applied both to binary [3] and to ternary (and even to multi) cluster-configurations. The results of these calculations can be combined with those on the energetic sta...

Extreme quadrupole deformation and clusterization

“…The question of the ternary clusterization for these shape isomers have been addressed in [47]. In particular, those possible ternary cluster-configurations have been determin- ed, which contain at least one double-magic clusters.…”

The concept of nuclear cluster forbiddenness

“…Of course, for the details one has to superimpose tunnel effects [18]. This conclusion was also obtained in [28,29]. The concept of forbiddennes, as will be exposed in this contribution, can be applied to heavy nuclei too, using the extensions of the harmonic oscillator picture, as mentioned above.…”

“…For example, in [14] preferences of clusterizations in ternary fission processes were investigated. Hyperdeformed states in 36 Ar were considered in [15], compared to experiments, and in [16] the clusterization in shape isomers of 58 Ni.…”

ALPHA-CLUSTER STATES POPULATED IN 24Mg + 12C

“…HD bands in 36 Ar and its related ternary clusterizations are predicted theoretically [11]. With the exception of the cluster decay of 56 Ni recently studied using charged particle spectroscopy [12], no evidence for ternary breakup has yet been reported [13] in light nuclei; the particle decay of 36 Ar SD bands (and other highly excited bands) is still unexplored.…”