Relations among neutral current couplings to test su(2) by u(1) gauge group structure

摘要

We propose a test of the validity of SU(2) ⊗ U(1) as the gauge group of weak and electromagnetic interactions. We find that, among the seven empirical neutral current couplings, there are two restrictions which do not rely on a particular model. The relations are 2( G V + G A ) + ( α + β ) + 3( γ + δ ) = 0 and 2 k − ( α + β ) + 3( γ + δ ) = 0, where where α , β , γ , δ ( G V , G A ) are the couplings measured in neutrino-hadron (electron) scattering and κ is obtained from interference experiments. We also find several inequalities. Comparison with present data is given.