β decay of odd- A nuclei with the interacting boson-fermion model based on the Gogny energy density functional

Abstract

The low-energy excitations and β decays of odd-A nuclei are studied within the interacting bosonfermion model (IBFM), based on the Gogny-D1M nuclear energy density functional (EDF). The constrained Hartree-Fock-Bogoliubov (HFB) approximation is employed to compute potential energy surfaces in terms of triaxial quadrupole degrees of freedom for even-even Xe and Ba nuclei in the mass A ≈ 130 region. The mean field approximation also provides spherical single-particle energies and occupation probabilities for the neighboring odd-A nuclei. Those quantities represent a microscopic input for spectroscopic calculations in odd-A Xe and Ba, Cs and La isotopes. The Gamow-Teller (GT) and Fermi (F) transition matrix elements, needed to compute β-decay log f t values are obtained without any phenomenological fitting. It is shown that both the low-lying states and β decays of the studied odd-A systems are described reasonably well within the employed theoretical framework.

$β$ decay of even-A nuclei within the interacting boson model based on nuclear density functional theory

“…The odd neutron occupying the 3s 1/2 orbital makes dominant contributions to the above mentioned pair configurations. This seems to be consistent with the fact that the 1/2 + 1 ground state of the neighboring odd-A nucleus 123 Xe is mostly accounted for by the 3s 1/2 neutron hole coupled to the even-even core 124 Xe [29].…”

“…In Ref. [29], we implemented the EDF-based interacting boson-fermion model (IBFM) [18,28] approach in the study of the β decay of odd-A nuclei. There we studied the allowed β decays, where the spin of the parent nucleus changes according to the ∆I = 0, ±1 rule and parity is conserved.…”

“…As in Ref. [29], we consider the β decays of those nuclei in the A ≈ 130 mass region. There are a number of (phenomenological) IBFM calculations for the low-lying states and β decay of odd-A nuclei.…”

β -decay rates of Rh115,117 into Pd115Ferretti1, Kotila2, Vsevolodovna3 et al. 2020Phys. Rev. C11021View full textAdd to dashboardCite

“…The investigation of such types of transitions, both on the theoretical and experimental sides, is extremely important. It can provide insight into the structure of heavy nuclei and serve as a test of the available nuclear structure models, including the interacting boson and bosonfermion models (IBM-2 and IBFM-2) [1][2][3][4][5][6][7][8][9], the quasiparticle random phase approximation (QRPA) [10][11][12][13][14][15], and the largescale nuclear shell model [16][17][18]. This is because the β-decay rates are very sensitive to the wave functions of the parent and daughter nuclei.…”

Critical point symmetry for odd-odd nuclei and collective multiple chiral doublet bands

“…Although the yrast and yrare bands in 132 La as a pair of doublet bands seem to follow the CPS description, the collective multiple chiral doublets predicted in theory remain to be revealed in experiments. Most recently, an algebraic model description of the chiral doublet bands in the even Cs isotopes was provided [83] in the framework of the interacting boson-fermion-fermion model (IBFFM-2) [29] with the similar particle-core (bosonfermion) coupling scheme and the same single-particle configuration πh 11/2 ⊗ νh −1 11/2 . It would be interesting to compare the CPS solutions with the IBFFM-2 calculations in the same situations.…”