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.

Analogue–antianalogue transition for the 11.14-MeV level in 49V

The g9/2 isobaric analogue resonance (IAR) is located at the excitation energy Ex = 11.139 MeV in 49V through the 48Ti(p, γ)49V reaction, (p, p1γ) angular distributions and the presence of the transition from the resonance to the 2.178-MeV (Jπ = 9/2+) level in 49V arc used to identify this resonance. The analogue–antianalogue M1 transition strength is found to be Γγ(M1) = 0.050 ± 0.009 eV or 0.2% of the single-particle estimate. This reduction in transition strength can be attributed partly to the fragmentation of the analogue and partly to the nonsingle-particle character of the antianalogue state.

Gamma decay of d5/2 isobaric analogue resonances in the 64Zn(p,γ) reaction

The resonances at Ep = 3.249 and 3.253 MeV in 64Zn(p,γ) are identified as fragments of the d5/2 isobaric analogue resonance from (p,p′γ) angular distributions. Gamma decay schemes and angular distributions are measured. In 65Ga, the level at 2.21 MeV is assigned a spin of Jπ = 5/2−. From angular distributions and symmetry potential considerations, the level at 2.82 MeV is considered to be the antianalogue state. The analogue–antianalogue transition strength is found to be compatible with single nucleon transfer data, thus showing that the interference effects from core polarized components arc negligible in this case.