ISB corrections to the superallowed Fermi transitions

The Fermi -decay proceeds between the ground state (g.s.) of the even-even nucleus and its isospin-analogue partner in the odd-odd nucleus, . The corresponding transition matrix element is:

The g.s. state in Eq. (17) is approximated by a projected state

(18) |

where is the g.s. of the even-even nucleus obtained in self-consistent MF calculations. The state is unambiguously defined by filling in the pairwise doubly degenerate levels of protons and neutrons up to the Fermi level. The daughter state is approximated by

where the self-consistent Slater determinant (or ) represents the so-called anti-aligned configuration, selected by placing the odd neutron and the odd proton in the lowest available time-reversed (or signature-reversed) s.p. orbits. The s.p. configuration manifestly breaks the isospin symmetry as schematically depicted in Fig. 1. The isospin projection from as expressed by Eq. (19) is essentially the only way to reach the states in odd-odd nuclei.

- Shape-current orientation
- Nearly degenerate -orbitals
- Theoretical uncertainties and error analysis
- The survey of ISB corrections in nuclei
- Confidence level test
- ISB corrections in nuclei