= Electron-positron annihilation into electron neutrinos
{title2=$e^+e^-\to\nu_e\bar\nu_e$}
The leading <Standard Model> gauge amplitudes are s-channel <Z boson> exchange and t-channel <W boson> exchange. They interfere. At collision energies well below the weak scale the <cross section> scales as $G_F^2s$. In an inclusive high-energy Born calculation, the forward W-exchange region gives a nonzero limiting scale of order $g^4/m_W^2$, unlike a fixed-angle estimate. Angular cuts and beam polarization can change comparisons with other annihilation channels.
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