Half-life of ${}_{}{}^{130}{}_{}{}^{}\mathrm{Te}$ double-β decay measured with geologically qualified samples

Tellurobismuthite (${\mathrm{Bi}}_2$${\mathrm{Te}}_3$) has been analyzed for Xe isotopes to determine the half-life for double-β decay of ${}_{}{}^{130}{}_{}{}^{}\mathrm{Te}$. Excess ${}_{}{}^{130}{}_{}{}^{}\mathrm{Xe}$ amounts to (6.18±0.18)×${10}^7$ atom/g with 47.8 wt. % Te, or (1.24±0.04)×${10}^{13}$ for the parent/daughter ratio ${}_{}{}^{130}{}_{}{}^{}\mathrm{Te}$${/}^{130}$Xe. With (9.3±1.1)×${10}^7$ yr for the Xe retention age of Te mineral, this provides (7.9±1.0)×${10}^{20}$ yr for the absolute half-life of ${}_{}{}^{130}{}_{}{}^{}\mathrm{Te}$ double-β decay. With this and a literature ratio ${\mathit{T}}_{1/2}$(130)/${\mathit{T}}_{1/2}$(128) of (3.52±0.11)×${10}^{\mathrm{-}4}$, we have (2.2±0.3)×${10}^{24}$ yr for the absolute half-life of ${}_{}{}^{128}{}_{}{}^{}\mathrm{Te}$ double-β decay. © 1996 The American Physical Society.