β+decay ofNe18and theftvalue of the0+→0−branch

The ${}_{}{}^{18}{}_{}{}^{}\mathrm{Ne}$→${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ $\beta$ decay was studied by measuring the ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ deexcitation $\gamma$ rays relative to the dominant superallowed $0^{+}$→$0^{+}$ (1042 keV) branch. The ratio of the intensity of the $0^{-}$ (1081 keV) deexcitation $\gamma$ ray relative to the 1042 keV deexcitation was found to be (2.97±0.22)×${10}^{-4\mathrm{}}$. An absolute $\beta$ branch $I_{\beta }=(2.14\mathrm{}\pm 0.26)\times {10}^{-3\mathrm{}}$% and $ft=(0.99\mathrm{}\pm 0.12)\times {10}^7$ sec for the $0^{+}$→$0^{-}$ $\beta$ decay branch were deduced. This value together with the existing result on the parity mixing of the $0^{+}$, $0^{-}$ doublet in ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ suggests $\left|F_{\pi }\right|=(0.4\mathrm{}\pm 1.1)\times {10}^{-6\mathrm{}}$. The absolute value for the $0^{+}$→$1^{+}$ (1700 keV) $\beta$ branch was deduced as $I_{\beta }=(0.183\mathrm{}\pm 0.006)$% and $ft=(3.19\mathrm{}\pm 0.12)\times {10}^4$ sec.