Systematic shell-model study of 
β
-decay properties and Gamow-Teller strength distributions in 
A≈40
 neutron-rich nuclei

We study Gamow-Teller strength distributions within a QRPA approach performed on top of a deformed Skyrme-Hartree-Fock+BCS single particle basis with the inclusion of residual spin-isospin interactions in both particle-hole and particle-particle channels. We focus our attention in several problems of interest in Nuclear Structure and Nuclear Astrophysics, such as the β-decay properties of proton-rich medium-mass nuclei of astrophysical interest and the deformation dependence of the Gamow-Teller strength distributions in neutron deficient Pb isotopes. We also discuss the role of deformation in the two-neutrino double beta decay.

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Realistic shell model description of beta decay

EPJ Web of Conferences ◽

10.1051/epjconf/201819402007 ◽

2018 ◽

Vol 194 ◽

pp. 02007

Author(s):

Angela Gargano ◽

Luigi Coraggio ◽

Luca De Angelis ◽

Tokuro Fukui ◽

Nunzio Itaco

Keyword(s):

Shell Model ◽

Beta Decay ◽

Electric Quadrupole ◽

Double Beta Decay ◽

Model Description ◽

Β Decay ◽

Decay Properties ◽

Model Study ◽

Many Body Perturbation Theory ◽

Transition Operators

In this paper, we extend our previous realistic shell-model study of Gamow-Teller strengths and double-β decay properties for nuclei around 132Sn to lighter mass nuclei. The effective shell-model Hamiltonian and transition operators are microscopically derived by way of many-body perturbation theory, without resorting to empirical parameters. Our main aim is to further check the reliability of our approach and verify its stability in other mass regions. Calculated energy spectra as well as electric-quadrupole and β-decay properties are presented for 76Ge and 82Se and compared with the experimental data, together with some results for 130Te and 136Xe already reported in our previous paper. Finally, some preliminary results of nuclear matrix elements responsible for the neutrinoless double beta decay, calculated by using the bare operator, are shown.

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Calculation of Gamow-Teller and two-neutrino double- β decay properties for Te130 and Xe136 with a realistic nucleon-nucleon potential

Physical Review C ◽

10.1103/physrevc.95.064324 ◽

2017 ◽

Vol 95 (6) ◽

Cited By ~ 26

Author(s):

L. Coraggio ◽

L. De Angelis ◽

T. Fukui ◽

A. Gargano ◽

N. Itaco

Keyword(s):

Nucleon Nucleon ◽

Β Decay ◽

Nucleon Potential ◽

Decay Properties ◽

Double Β Decay ◽

Gamow Teller

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Gamow-Teller strengths of some sd-shell nuclei in the shell model framework

Revista Mexicana de Física ◽

10.31349/revmexfis.66.330 ◽

2020 ◽

Vol 66 (3 May-Jun) ◽

pp. 330 ◽

Cited By ~ 1

Author(s):

S. M. Obaid ◽

H. M. Tawfeek

Keyword(s):

Shell Model ◽

Model Space ◽

Transition Strength ◽

Model Framework ◽

Model Calculations ◽

Effective Interactions ◽

Calculated Distribution ◽

Gamow Teller ◽

Sd Model ◽

Strength Distributions

The nuclear Gamow-Teller (GT) transition strength distributions B(GT)have been studied for some sd-shell nuclei in the (3He, t) charge-exchangereactions. The shell model calculations were performed by employing theUSDA and USDB effective interactions in the sd-model space. The results of B(GT) calculations reproduce the the experimental Gamow-Tellerstrength distributions well, while the calculated distribution of summedGT transition strengths were closely reproduce the observed ones.

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Gamow-Teller transitions of neutron-rich N = 82, 81 nuclei by shell-model calculations

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptab022 ◽

2021 ◽

Author(s):

Noritaka Shimizu ◽

Tomoaki Togashi ◽

Yutaka Utsuno

Keyword(s):

Shell Model ◽

Large Scale ◽

Β Decay ◽

Excitation Energies ◽

Pauli Blocking ◽

Model Calculations ◽

Model Hamiltonian ◽

R Process ◽

Gamow Teller ◽

Valence Proton

Abstract β-decay half-lives of neutron-rich nuclei around N = 82 are key data to understand the r-process nucleosynthesis. We performed large-scale shell-model calculations in this region using a newly constructed shell-model Hamiltonian, and successfully described the low-lying spectra and half-lives of neutron-rich N = 82 and N = 81 isotones with Z = 42 − 49 in a unified way. We found that their Gamow-Teller strength distributions have a peak in the low-excitation energies, which significantly contributes to the half-lives. This peak, dominated by ν0g7/2 → π0g9/2 transitions, is enhanced on the proton deficient side because the Pauli-blocking effect caused by occupying the valence proton 0g9/2 orbit is weakened.

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Shell model results for nuclear β−-decay properties of sd-shell nuclei

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptaa012 ◽

2020 ◽

Vol 2020 (3) ◽

Cited By ~ 2

Author(s):

Anil Kumar ◽

Praveen C Srivastava ◽

Toshio Suzuki

Keyword(s):

Shell Model ◽

Effective Field Theory ◽

Effective Field ◽

Coupled Cluster ◽

Nuclear Shell Model ◽

Chiral Effective Field Theory ◽

Β Decay ◽

Decay Properties ◽

Nuclear Shell ◽

Theoretical Results

Abstract We evaluate the allowed $\beta^-$-decay properties of nuclei with $Z = 8$–$15$ systematically under the framework of the nuclear shell model using the valence space Hamiltonians derived from modern ab initio methods, such as in-medium similarity renormalization group and coupled-cluster theory. For comparison we also show results obtained with fitted interaction derived from chiral effective field theory and phenomenological universal $sd$-shell Hamiltonian version B interaction. We have performed calculations for O $\rightarrow$ F, F $\rightarrow$ Ne, Ne $\rightarrow$ Na, Na $\rightarrow$ Mg, Mg $\rightarrow$ Al, Al $\rightarrow$ Si, Si $\rightarrow$ P, and P $\rightarrow$ S transitions. Theoretical results for $B(GT)$, $\log ft$ values, and half-lives are discussed and compared with the available experimental data.

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