Beta-Gamma Directional Correlation in the Decay ofCo60andNa22

The differential and integral beta-gamma directional correlations in the decay of ${\mathrm{Co}}^{60}$ and ${\mathrm{Na}}^{22}$ have been measured with scintillation counters. Both beta transitions are allowed but have high $\mathrm{ft}$ values. Therefore, small anisotropies are not excluded. In the case of ${\mathrm{Co}}^{60}$ the anisotropy was found to be zero for all beta energies above 0.06 Mev; the integral anisotropy was measured to be $A=-0.0003\mathrm{}\pm 0.0017$ (standard deviation). In the case of ${\mathrm{Na}}^{22}$ the results seem to indicate an energy dependence of the anisotropy; the value is uncertain because of coincidences between positrons and annihilation quanta.