Testing interacting boson model cores through particle-core coupling: Negative parity states in the odd-mass Tl and Au isotopes

In order to investigate negative parity states, it is necessary to consider negative parity-bosons additionally to the usual [Formula: see text]- and [Formula: see text]-bosons. The dipole and octupole degrees of freedom are essential to describe the observed low-lying collective states with negative parity. An extended interacting boson model (IBM) that describes pairing interactions among s, p, d and f-boson based on affine [Formula: see text] Lie algebra in the quantum phase transition (QPT) field, such as spd-IBM, sdf-IBM and spdf-IBM, is composed based on algebraic structure. In this paper, a solvable extended transitional Hamiltonian based on affine [Formula: see text] Lie algebra is proposed to describe low-lying positive and negative parity states between the spherical and deformed gamma-unstable shape. Three model of new algebraic solution for even–even nuclei are introduced. Numerical extraction to low-lying energy levels and transition rates within the control parameters of this evaluated Hamiltonian are presented for various [Formula: see text] values. We reproduced the positive and negative parity states and our calculations suggest that the results of spdf-IBM are better than spd-IBM and sdf-IBM in this literature. By reproducing the experimental results, the method based on signature of the phase transition such as level crossing in the lowest excited states is used to provide a better description of Ru isotopes in this transitional region.

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Nuclear Gamma-soft Character in ¹²⁸Ba

European Journal of Applied Physics ◽

10.24018/ejphysics.2021.3.3.54 ◽

2021 ◽

Vol 3 (3) ◽

pp. 16-20

Author(s):

I. Hossain ◽

Hewa Y. Abdullah ◽

I. M. Ahmed ◽

Fadhil I. Sharrad

Keyword(s):

Energy Level ◽

Vector Boson ◽

Negative Parity ◽

Measured Data ◽

Interacting Boson Model ◽

Parity Band ◽

Boson Model ◽

Experimental Values ◽

Negative Parity Band

We report the properties of gamma soft O(6) of 128Ba isotones with neutron N = 72 using Interacting Vector Boson Model (IVBM), interacting Boson Model (IBM-1), Bohr-Mottelson Model (BM), and Doma-El-Gendy (D-G) relation. The first energy level ( ) and ratio have been investigated which show that 128Ba has gamma-soft character. The curves Eγ/Vs.J of E-GOS of even 128Ba nucleus were compared with the standard curves of vibrational, gamma soft and rotational limits. The staggering factors were studied of available measured data of 128Ba nucleus. The yrast levels of this isotope are calculated by the model of VBMI, IBM-1, BM and D-G and they were compared by measured data. The negative parity band of 128Ba was calculated by IVBM and BM model and compared with experimental values.

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Structure of the low-lying positive and negative parity states in even–even 144−154Nd isotopes

International Journal of Modern Physics E ◽

10.1142/s0218301319501076 ◽

2019 ◽

Vol 28 (12) ◽

pp. 1950107

Author(s):

Hussein N. Qasim ◽

Falih H. Al-Khudair

Keyword(s):

Potential Energy Surfaces ◽

Transition Probability ◽

Model Space ◽

Negative Parity ◽

Energy Spectra ◽

Interacting Boson Model ◽

Nd Isotopes ◽

Nd Isotope ◽

Boson Model ◽

Energy Surfaces

The low-lying positive and negative parity states of even–even [Formula: see text]Nd isotopes are studied using the interacting boson model (IBM). The negative parity states are involved within the IBM model by adding a single angular momentum ([Formula: see text]) boson with intrinsic negative parity [Formula: see text]-boson to [Formula: see text] and [Formula: see text]-bosons model space. For these nuclei, the potential energy surfaces [Formula: see text], transition probability [Formula: see text], [Formula: see text] and [Formula: see text] are calculated. Phase transition from the [Formula: see text] limit to the [Formula: see text] limit is observed in the chain and the critical point has been determined for [Formula: see text]Nd isotope. It is found that the calculated positive and negative parity energy spectra of Nd-isotopes agree well with the experimental data.

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"Beat" Patterns of Odd-Even Staggering in Octupole Bands of Light Actinides

HNPS Proceedings ◽

10.12681/hnps.2196 ◽

2019 ◽

Vol 11 ◽

Author(s):

Dennis Bonatsos ◽

C. Daskaloyannis ◽

S. B. Drenska ◽

N. Karoussos ◽

N. Minkov ◽

...

Keyword(s):

Vector Boson ◽

Negative Parity ◽

Interacting Boson Model ◽

Algebraic Models ◽

Ground State Band ◽

Parity Band ◽

State Band ◽

Boson Model ◽

The Difference ◽

Negative Parity Band

The Δ I = 1 staggering (odd-even staggering) in octupole bands of light actinides. is found to exhibit a "beat" behaviour as a function of the angular momentum J, forcing us to revise the traditional belief that this staggering decreases gradually to, zero and then remains at this zero value. Various algebraic models (spf-Interacting Boson Model, spdf-IBM, Vector Boson Model, Nuclear Vibron Model) predict in their su(3) limits constant staggering for this case, being thus unable to describe the "beat" behaviour. An explanation of the "beat" behaviour is given in terms of two Dunham expansions (expansions in terms of powers of I ( I + 1) ) with slightly different sets of coefficients for the ground state band and the negative parity band, the difference in the values of the coefficients being attributed to Coriolis couplings to other negative parity bands.

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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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Octupole and quadrupole modes in radon isotopes using the proton-neutron interacting boson model

Physical Review C ◽

10.1103/physrevc.104.014308 ◽

2021 ◽

Vol 104 (1) ◽

Author(s):

O. Vallejos ◽

J. Barea

Keyword(s):

Interacting Boson Model ◽

Boson Model ◽

Radon Isotopes

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Role of Single-Particle Energies in Microscopic Interacting Boson Model Double Beta Decay Calculations

Universe ◽

10.3390/universe7030066 ◽

2021 ◽

Vol 7 (3) ◽

pp. 66

Author(s):

Jenni Kotila

Keyword(s):

Beta Decay ◽

Single Particle ◽

Field Potential ◽

Double Beta Decay ◽

Interacting Boson Model ◽

Model Calculations ◽

Single Particle Level ◽

Particle Level ◽

Boson Model

Single-particle level energies form a significant input in nuclear physics calculations where single-particle degrees of freedom are taken into account, including microscopic interacting boson model investigations. The single-particle energies may be treated as input parameters that are fitted to reach an optimal fit to the data. Alternatively, they can be calculated using a mean field potential, or they can be extracted from available experimental data, as is done in the current study. The role of single-particle level energies in the microscopic interacting boson model calculations is discussed with special emphasis on recent double beta decay calculations.

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