Neutrino scattering on an antiquark
= Neutrino scattering on an antiquark
{title2=$d\sigma_{\bar u}/dy=G_F^2s(1-y)^2/\pi$}
For a massless <neutrino> scattering on an unpolarized up <antiquark> through the <Fermi interaction>, $d\sigma/dy=G_F^2s(1-y)^2/\pi$. The corresponding down-quark channel has $d\sigma/dy=G_F^2s/\pi$. Their difference follows from the <chiral weak-current trace contraction>. The <parton distribution functions> weight these rates in a hadron.