The $\beta$-ray angular correlations for the spin alignments of ${}^8\mathrm{Li}$ and ${}^8\mathrm{B}$ have been observed in order to test the conserved vector current (CVC) hypothesis. The alignment correlation terms were combined with the known $\beta$-$\alpha$ angular correlation terms to determine all the matrix elements contributing to the correlation terms. The weak magnetism term, $7.5\pm 0.2$, deduced from the $\beta$-ray correlation terms was consistent with the CVC prediction $7.3\pm 0.2$, deduced from the analog-$\gamma$ decay measurement based on the CVC hypothesis. However, there was no consistent CVC prediction for the second-forbidden term associated with the weak vector current. The experimental value for the second-forbidden term was $1.0\pm 0.3$, while the CVC prediction was $0.1\pm 0.4$ or $2.1\pm 0.5$.

• Received 20 January 2011

DOI:https://doi.org/10.1103/PhysRevC.83.065501