Isospin corrections to super-allowed beta decays in nuclei

20th International School on Nuclear Physics, Neutron Physics and Applications

Auerbach, N.^1

School of Physics and Astronomy, Tel Aviv University, Tel Aviv

69978, Israel^1

关键词: Beta decay;    Beta decay matrix element;    Impurities in;    Isobaric analog state;    Isospin;    Mass numbers;    Perturbation theory;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/533/1/012001/pdf
DOI  :  10.1088/1742-6596/533/1/012001

来源: IOP

【 摘 要 】

Isospin corrections to the super-allowed beta decay matrix elements are evaluated in perturbation theory using the notion of the giant isovector monopole state. The calculation avoids the separation into different contributions and therefore presents a consistent, systematic and more transparent approach. Explicit expressions for δcas a function of the mass number A are derived. These corrections affect the values of the Vudmatrix element in the Cabbibo-Maskawa-Kobayashi matrix. Also, it is pointed out that in some nuclei with a low number of excess neutrons (protons) Coulomb mixing with the anti-analog state can introduce significant isospin impurities in the isobaric analog state.