Beta-ray angular distributions of spin aligned 8Li and 8B

The alignment correlation terms in the β -ray angular distributions from spin aligned 8 Li and 8 B have been measured precisely. The difference of these terms between the mirror pair is compared with the prediction. As a result, the G -parity violating induced tensor term is found to be small. The significant contribution from the second-forbidden matrix elements is shown by comparing with the β - α correlation coefficients.