Calculations of bound-state ${\beta }^{-}$-decay half-lives of highly ionized ${}^{163}$Dy${}^{66+}$, ${}^{187}$Re${}^{75+}$ and ${}^{205}$Tl${}^{81+}$

Abstract

We propose a theoretical method to calculate the bound-state $\beta$-decay half-lives of highly-ionized atoms, which is based on the combination of the Takahashi-Yokoi model and our recently-developed projected shell model that can take into account both allowed and first-forbidden transitions of nuclear $\beta$ decay. Three examples that are of much experimental interests, ${}^{163}$Dy${}^{66+}$, ${}^{187}$Re${}^{75+}$ and ${}^{205}$Tl${}^{81+}$ are taken for calculations. The ground and low-lying states of related nuclei are described reasonably. The bound-state $\beta$-decay half-lives of ${}^{163}$Dy${}^{66+}$ and ${}^{187}$Re${}^{75+}$ are described within a factor of two and four by our calculations without and with the quenching factors in allowed and first-forbidden transitions. The bound-state $\beta$-decay half-life of the last $s$-process branching point ${}^{205}$Tl${}^{81+}$ is predicted to be 58 and 305 days for cases without and with the quenching factors in calculations. The presented method provides a theoretical way to calculate systematically the bound-state $\beta$-decay half-lives of nuclei from light to heavy ones including odd-mass and even-mass cases for the first time.

Comments: 8 pages, 6 figures, 2 tables, Comments and criticisms are welcome