Beta-Gamma Circular Polarization Correlation Experiments

A circular polarization analyzer for $\gamma$ rays is described. Measurements on circular polarization of bremsstrahlung due to $\beta$ particles from ${\mathrm{P}}^{32}$ and ${\mathrm{Tm}}^{170}$ agree with previous and concurrent measurements and, together with ${\mathrm{Co}}^{60}$ circular polarization correlation studies, establish a check on the calculated calibration curve of the analyzer. We have studied the $\beta -\gamma$ circular polarization correlation in the following allowed $j-j$ transitions: ${\mathrm{Na}}^{24}$, ${\mathrm{Sc}}^{44}$, ${\mathrm{Sc}}^{46}$, ${\mathrm{V}}^{48}$, and ${\mathrm{Co}}^{58}$. The result for ${\mathrm{Sc}}^{46}$ indicates the presence of a strong interference between Gamow-Teller and Fermi couplings. The $\beta$ interaction, therefore, should contain a combination of $S$ and $T$, or (and) $V$ and $A$, interactions with small or no phase difference between the interaction constants. If one assumes maximum interference, our experiments give information on the ratio of Gamow-Teller to Fermi interaction. The once-forbidden transition ${\mathrm{Au}}^{198}$ gives the maximum possible asymmetry. All results are in agreement with the 2-component neutrino theory and the assumption of $V$, $A$ or alternatively $S$, $T$, $P$ interaction.