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Shell-model calculations of two-neutrino double-beta decay rates of $^{48}$Ca with GXPF1A interaction

M. Horoi·S. Stoica·B. A. Brown
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Abstract

The two-neutrino double beta decay matrix elements and half-lives of $^{48}$Ca, are calculated within a shell-model approach for transitions to the ground state and to the $2^+$ first excited state of $^{48}$Ti. We use the full $pf$ model space and the GXPF1A interaction, which was recently proposed to describe the spectroscopic properties of the nuclei in the nuclear mass region A=47-66. Our results are $T_{1/2}(0^{+}\to 0^{+})$ = $3.3\times 10^{19}$ $yr$ and $T_{1/2}(0^{+}\to 2^{+})$ = $8.5\times 10^{23}$ $yr$. The result for the decay to the $^{48}$Ti 0$^+$ ground state is in good agreement with experiment. The half-life for the decay to the 2$^+$ state is two orders of magnitude larger than obtained previously.

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M. Horoi, S. Stoica, B. A. Brown. 2007-01-25. Shell-model calculations of two-neutrino double-beta decay rates of $^{48}$Ca with GXPF1A interaction. https://doi.org/10.1103/physrevc.75.034303

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