The anomalous ¹⁴C-dating β decay problem revisited

The anomalous inhibition of $^{14}$C-dating $\beta$ decay rate is restudied in terms of shell-model calculations in the $jj$ coupling scheme with both realistic and empirical Hamiltonians. It is seen that the accidental cancellation of the decay strength is dominated by the mixing effect of two configurations of the final state wave function, $|0p^{-2}_{1/2}>$ and $|0p_{3/2}^{-1}0p_{1/2}^{-1}>$. By decomposing the effective interactions into different tensor components, it is clearly seen that the mixing is largely induced by the tensor force. The failure of realistic calculations in reproducing the inhibition may be related to its ill description of the monopole component rather than the tensor force.