Vanishing Fermi to Gamow-Teller Mixing Ratio of the ß⁺ Decay of ⁵⁸Co

Abstract

Since 1956, fourteen experimentally-deduced values of the Fermi to Gamow-Teller mixing ratio y = CvMF/CAMGT were published, varying from 0.05 to -0.36 with most values consistent with y = 0, particularly those from recent measurements. Our calculation, using the Nilsson model, yields y= 2.07 x 10-4, which can be taken as zero. Our result is therefore consistent with time-reversal invariance. Furthermore, the vanishing value of y arises both from the ΔT selection rule and the ΔK selection rule