Composite-W-boson couplings

The couplings of W bosons to leptons and quarks are calculated by making an ansatz for the composite-W-boson Bethe-Salpeter amplitude. The ansatz is constructed to be consistent in the nonrelativistic limit with the W-boson wave function as generated from a potential model. The γ$W^0$ mixing parameter λ and the weak coupling g are derived. The only free parameter is the mass of the leptonic scalar preon $m_s$ which is found to be ∼2 TeV to correctly reproduce ${\sin }^2$ ${\mathrm{\theta }}_{\mathrm{W}}$. It is shown that ${\sin }^2$ ${\mathrm{\theta }}_{\mathrm{W}}$ is only indirectly related to the wave function at the origin.