= Electron-positron annihilation into W-boson pairs
{title2=$e^+e^-\to W^+W^-$}
At tree level in the <Standard Model>, the diagrams are s-channel <photon>, <Z boson> and <Higgs boson> exchange, and t-channel <electron neutrino> exchange. The Higgs contribution couples to the <Electron> through its small <Yukawa coupling>. In a zero-electron-mass approximation that diagram vanishes, leaving the three gauge diagrams. The gauge contributions interfere; their sum has the high-energy behavior required by the electroweak gauge structure.
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