Estimate of the parity-violatingα-decay width of the0+,T=1state ofLi6

A full two-body shell-model calculation has been used to estimate the pion-exchange contribution to the parity-violating $\alpha$ decay of the $0^{+}$, $T=1\mathrm{}$ state of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$. For a neutral-current-induced weak pion amplitude equal to the "best" value given by Desplanques, Donoghue, and Holstein, the $\alpha$ width is 1.3×${10}^{-8\mathrm{}}$ eV. There is no contribution in lowest order from the intrinsic parity impurity in the $\alpha$ particle, but there is a small contribution from the deuteron.