Binary cluster model calculations for 20Ne and 44Ti nuclei

The elastic scattering data of [Formula: see text] and [Formula: see text] systems at [Formula: see text] = 32.2–146 MeV and [Formula: see text] = 24.1–49.5 MeV energies have been analyzed with double-folding (DF) potential in optical model formalism in order to investigate the cluster structures of [Formula: see text]Ne and [Formula: see text]Ti nuclei. The deduced DF potentials between [Formula: see text] and [Formula: see text]O as well as [Formula: see text] and [Formula: see text]Ca have been used for obtaining the excitation energies and [Formula: see text]-decay widths of [Formula: see text]Ne and [Formula: see text]Ti in Gamow code, but the reasonable results could not be obtained. Thus, the real parts of DF potentials which are in the best agreement with experimental data have been fitted with the squared-Woods–Saxon (WS2) potential parameters to calculate the [Formula: see text]-decay widths of [Formula: see text]Ne and [Formula: see text]Ti with Wentzel–Kramers–Brillouin (WKB) approach. The nuclear potential sets obtained in WKB calculations are also used for Gamow code calculations. We take into account the deformation and orientation of [Formula: see text]Ca nucleus to examine their influence on both the excitation energies and decay widths of [Formula: see text]Ti. Besides, by using the binary cluster model the rotational band energies and electromagnetic transition probabilities (BE2)s according to angles are also reproduced for both nuclei. The obtained results showed that the binary cluster model is very useful to understand the observables of [Formula: see text]Ne and [Formula: see text]Ti nuclei. Although only spherical calculations are made for [Formula: see text]Ne ([Formula: see text] + [Formula: see text]O), the deformation in [Formula: see text]Ca would be important for the understanding of [Formula: see text]Ti ([Formula: see text] + [Formula: see text]Ca) cluster structure. The mechanism presented here would also be applied to understand the cluster structures in heavy nuclei.

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ALPHA-CLUSTER STRUCTURE IN 13C

International Journal of Modern Physics E ◽

10.1142/s0218301308011124 ◽

2008 ◽

Vol 17 (10) ◽

pp. 2076-2080

Author(s):

TOORU YOSHIDA ◽

NAOYUKI ITAKAGI ◽

TAKAHARU OTSUKA

Keyword(s):

Cluster Model ◽

Transition Probabilities ◽

Cluster Structure ◽

Model Space ◽

Orbit Interaction ◽

Valence Neutron ◽

Spin Orbit ◽

Breaking Effect ◽

Spin Orbit Interaction ◽

Alpha Cluster

We study the structure of low-lying states of 13 C with a microscopic cluster model. In addition to the 3α-n model space, the breaking effect of one of the α-clusters due to the spin-orbit interaction is also taken into account. The iso-scalar E0 transition probabilities from the ground 1/2- state to the excited 1/2- states have been shown to be large associated with the cluster structure of these states. However the values are small due to the effect of one additional valence neutron compared to the case of the second 0+ state in 12 C .

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Testing the core-cluster model calculations for some heavy deformed nuclei

International Journal of Modern Physics E ◽

10.1142/s0218301319500496 ◽

2019 ◽

Vol 28 (07) ◽

pp. 1950049

Author(s):

L. I. Abou-Salem ◽

K. E. Abdelmageed ◽

I. A. Elmashad ◽

R. Al Allam

Keyword(s):

Experimental Data ◽

Cluster Model ◽

Theoretical Calculations ◽

Transition Probability ◽

Parent Nucleus ◽

Negative Parity ◽

Excitation Energies ◽

Model Calculations ◽

The Core ◽

Core Cluster

In this work, the spectra of some even–even isotopes are studied by selecting core-cluster decomposition of the parent nucleus. The considered nuclei lie in the rare-earth and the transition metal regions. The Schrödinger equation can be solved using Bohr–Sommerfeld relation and the modified Woods–Saxon beside Coulomb potentials to reproduce the spectra of these isotopes with mass number [Formula: see text]. The theoretical calculations of the excitation energies of the ground state rotational band are compared to the experimental data. The cluster model calculations show a good agreement with the experimental data for the transitional and rotational nuclei more than the vibrational nuclei. Some negative parity bands of the chosen nuclei are studied. The core-cluster charge products are correlated with the transition probability [Formula: see text].

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Cluster-model calculations of exotic decays from heavy nuclei

Physical Review C ◽

10.1103/physrevc.39.2097 ◽

1989 ◽

Vol 39 (5) ◽

pp. 2097-2100 ◽

Cited By ~ 49

Author(s):

B. Buck ◽

A. C. Merchant

Keyword(s):

Cluster Model ◽

Heavy Nuclei ◽

Model Calculations

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Calculation of the Electric Quadrupole Moment of 6Li and 7Li in Shell Model and Cluster Model

Jordan Journal of Physics ◽

10.47011/14.4.7 ◽

2021 ◽

Vol 14 (4) ◽

pp. 333-338

Keyword(s):

Wave Function ◽

Shell Model ◽

Quadrupole Moment ◽

Cluster Model ◽

Particle System ◽

Cluster Structure ◽

Electric Quadrupole ◽

Experimental Results ◽

Electric Quadrupole Moment ◽

Model Calculations

Abstract: In this paper, we have investigated electric quadrupole moment of (_^6)Li and (_^7)Li in both shell model and cluster model. In shell model, the nuclei (_^6)Li and (_^7)Li can be modeled as one core plus nucleons. Nucleons outside the closed shell can be considered as a two- and three-particle system. In cluster structure, we have selected alpha clusters and triton or deuteron in interaction with alpha cluster ((_^7)Li and (_^6)Li involving α+(_^3)H and α+(_^2)H, respectively). By solving Schrödinger equation and using suitable potential for interaction between particles by applying Nikiforov-Uvarov method, potential coefficients have been computed. Then, we have calculated the energy and wave function for nuclei(_^6)Li and (_^7)Li and compared the results obtained with experimental results. By having the wave function, we can obtain the quadrupole moment. These values are compared with predictions from shell-model and cluster-model calculations. Although the difference between them is small, the electric quadrupole moment results in the cluster model are in good agreement with experimental results. Keywords: Electric quadrupole moment, Shell-model, Cluster-model, Li isotopes, Non-relativistic equation.

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Bose–Einstein condensation of dilute alpha clusters above the four-α threshold in 16O in the field theoretical superfluid cluster model

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptaa117 ◽

2020 ◽

Vol 2020 (9) ◽

Author(s):

J Takahashi ◽

Y Yamanaka ◽

S Ohkubo

Keyword(s):

Cluster Model ◽

Level Structure ◽

Cluster Structure ◽

Einstein Condensation ◽

Condensation Rate ◽

Excitation Energies ◽

Energy Level Structure ◽

Bose Einstein Condensation ◽

Alpha Cluster ◽

Bose Einstein

Abstract Observed well-developed $\alpha$ cluster states in $^{16}$O located above the four-$\alpha$ threshold are investigated from the viewpoint of Bose–Einstein condensation of $\alpha$ clusters by using a field-theoretical superfluid cluster model in which the order parameter is defined. The experimental energy levels are reproduced well for the first time by calculation. In particular, the observed 16.7 MeV $0_7^+$ and 18.8 MeV $0_8^+$ states with low-excitation energies from the threshold are found to be understood as a manifestation of the states of the Nambu–Goldstone zero-mode operators, associated with the spontaneous symmetry-breaking of the global phase, which is caused by the Bose–Einstein condensation of the vacuum 15.1 MeV $0^+_6$ state with a dilute well-developed $\alpha$ cluster structure just above the threshold. This gives evidence of the existence of the Bose–Einstein condensate of $\alpha$ clusters in $^{16}$O. It is found that the emergence of the energy level structure with a well-developed $\alpha$ cluster structure above the threshold is robust, almost independently of the condensation rate of $\alpha$ clusters under significant condensation rate. The finding of the mechanism that causes the level structure that is similar to $^{12}$C to emerge above the four-$\alpha$ threshold in $^{16}$O reinforces the concept of Bose–Einstein condensation of $\alpha$ clusters in addition to $^{12}$C.

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F-SPIN SYMMETRY BREAKING: APPLICATION TO THE U(5) AND SU(3) LIMIT

International Journal of Modern Physics A ◽

10.1142/s0217751x8900159x ◽

1989 ◽

Vol 04 (15) ◽

pp. 3907-3938 ◽

Cited By ~ 6

Author(s):

C. DE COSTER ◽

K. HEYDE

Keyword(s):

Spin Structure ◽

Transition Probabilities ◽

Spin Symmetry ◽

Wave Functions ◽

Spin Vector ◽

Excitation Energies ◽

Electromagnetic Transition ◽

First Order ◽

Mixed Symmetry ◽

Analytic Expressions

Starting from the U(5) and SU(3) dynamic symmetries, perturbations on an F-spin scalar IBM-2 Hamiltonian are studied. The parameters describing the perturbations are chosen such as to introduce only the F-spin vector and the F-spin tensor terms of rank two. Effects on the F-spin structure of the wave functions, excitation energies and electromagnetic transition probabilities are studied for the lowest symmetric and mixed-symmetry states. If possible, numerical results are compared to analytic expressions derived via the first-order perturbation calculations.

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Energy Levels and Electromagnetic Transition of 90-94mo Nuclei Using Ibm-1

10.32792/utq/utjsci/vol7/2/32 ◽

2020 ◽

pp. 149-152

Keyword(s):

Experimental Data ◽

Transition Probability ◽

Energy Levels ◽

Dynamical Symmetry ◽

Interacting Boson Model ◽

Excitation Energies ◽

Electromagnetic Transition ◽

Boson Model ◽

Energy States ◽

Good Agreement

The energy states for the J , b , ɤ bands and electromagnetic transitions B (E2) values for even – even molybdenum 90 – 94 Mo nuclei are calculated in the present work of "the interacting boson model (IBM-1)" . The parameters of the equation of IBM-1 Hamiltonian are determined which yield the best excellent suit the experimental energy states . The positive parity of energy states are obtained by using IBS1. for program for even 90 – 94 Mo isotopes with bosons number 5 , 4 and 5 respectively. The" reduced transition probability B(E2)" of these neuclei are calculated and compared with the experimental data . The ratio of the excitation energies of the 41+ to 21+ states ( R4/2) are also calculated . The calculated and experimental (R4/2) values showed that the 90 – 94 Mo nuclei have the vibrational dynamical symmetry U(5). Good agreement was found from comparison between the calculated energy states and electric quadruple probabilities B(E2) transition of the 90–94Mo isotopes with the experimental data .

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