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Low-lying Gamow-Teller transitions in spherical nuclei

The Pyatov Method has been used to study the low-lying Gamow-Teller transitions in the mass region of 98 ⩽ A ⩽ 130. The eigenvalues and eigenfunctions of the total Hamiltonian have been solved within the framework of proton-neutron quasiparticle random-phase approximation. The low-lying β decay log(ft) values have been calculated for the nuclei under consideration.

Deformation effects on isospin mixing and isobar analogue resonance for 74−80Kr isotopes

Pyatov’s method has been applied to investigate Fermi beta transitions in deformed 74–80Kr isotopes. This self-consistent method, which was used to study the isobar analogue states in the spherical odd-odd nuclei, has to date not been applied for the isobar analogue states in deformed nuclei. The nucleon-nucleon residual interaction has been included so that the broken isospin symmetry in the mean field approximation has been restored and the strength parameter of the effective interaction has been taken out to be a free parameter. The energies and wave functions of the isobaric analogue excitations in 74–80Rb isotopes have been obtained within the framework of the pnQRPA method. The probability of the isospin mixing in the ground states and the centroid energies of the isobar analogue resonance have been presented and the deformation effects on these quantities have been quantified.

The study of Gamow-Teller transition strength for some Fe and Ni isotopes

The method developed by Pyatov and Salamov has been used to study the Gamow-Teller transition strength in the iron mass region nuclei. Calculations have been performed within the framework of the proton-neutron quasiparticle random-phase approximation with separable Gamow-Teller residual interactions. The obtained results have been compared with other theoretical results and the corresponding experimental data.

Isospin mixing and Fermi transitions for some deformed nuclei

Abstract:We have tried to give a self-consistent explanation of isospin mixing and Fermi beta decays for 54 ≤ Z ≤ 68 deformed nuclei. The effect of isospin impurity in nuclear ground states on Fermi beta transitions has been investigated considering the restoration of symmetry violations stemming from the mean field approximation. The isobar analogue excitations in neighbor odd-odd nuclei have been obtained by following the proton-neutron quasiparticle random phase approximation (pnQRPA) procedure. The dependence of isospin admixture probability on the deformation parameter has been determined for various isotopes of Z = 54–68 nuclei. Then the variations of isobar analogue state energies and the β decay log(ft) values with deformation parameter have been calculated for the same nuclei. Thus, the influences of the isospin symmetry violations on Fermi transitions can be clearly understood.