Test of the Nature of the Vector Interaction inβDecay

An experiment is proposed to test the theory recently advanced by Feynman and Gell-Mann on the vector interaction in $\beta$ decay. According to the theory, the Fermi coupling constant is not appreciably altered by renormalization, in agreement with experiment. A further property of the theory is exploited here, that analogous $\gamma$ and $\beta$ transitions in light nuclei have proportional matrix elements, as far as the $V$ interaction is concerned. In particular, the $V$ interaction gives rise to "weak magnetism" analogous to the magnetic effects that induce the emission of $M1\mathrm{}$ photons. This "weak magnetism" obeys Gamow-Teller selection rules and interferes with the $A$ coupling, distorting the spectra of high-energy $\beta$ transitions with $\Delta J=1\mathrm{}$ (no).