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arXiv · 0904.3673

Isospin corrections for superallowed Fermi beta decay in self-consistent relativistic random phase approximation approaches

Haozhao Liang·Nguyen Van Giai·Jie Meng
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Abstract

Self-consistent random phase approximation (RPA) approaches in the relativistic framework are applied to calculate the isospin symmetry-breaking corrections $δ_c$ for the $0^+\to0^+$ superallowed transitions. It is found that the corrections $δ_c$ are sensitive to the proper treatments of the Coulomb mean field, but not so much to specific effective interactions. With these corrections $δ_c$, the nucleus-independent $\mathcal{F}t$ values are obtained in combination with the experimental $ft$ values in the most recent survey and the improved radiative corrections. It is found that the constancy of the $\mathcal{F}t$ values is satisfied for all effective interactions employed. Furthermore, the element $V_{ud}$ and unitarity of the Cabibbo-Kobayashi-Maskawa matrix are discussed.

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Haozhao Liang, Nguyen Van Giai, Jie Meng. 2009-06-19. Isospin corrections for superallowed Fermi beta decay in self-consistent relativistic random phase approximation approaches. https://doi.org/10.1103/physrevc.79.064316

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