The Beta-Decay Interaction

The recent identifications of two beta-decays as 0-to-0 transitions proves that the beta-decay interaction must contain a component obeying Fermi selection rules. Evidence is presented regarding the relative strengths of the Fermi- and Gamow-Teller interactions, and experiments are suggested to improve our knowledge of these strengths. It is pointed out that the ${\mathrm{He}}^6$ $\mathrm{ft}$ value does not give significant information about the beta-decay interaction. An experiment is proposed to determine the nature (scalar or polar vector) of the Fermi interaction.