Comparison ofνnandνpCharged-Current Cross Sections from High-Energy Neutrino Interactions in Deuterium

Abstract

From an analysis of the reaction ${\ensuremath{\nu}}_{\ensuremath{\mu}}+d\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}+X$, obtained from an exposure of the Fermilab 15-ft deuterium-filled bubble chamber, the ratios of charged-current cross sections for ${E}_{\ensuremath{\nu}}g10$ GeV are determined to be $\frac{\ensuremath{\sigma}(\ensuremath{\nu}n)}{\ensuremath{\sigma}(\ensuremath{\nu}p)}=2.03\ifmmode\pm\else\textpm\fi{}0.28$ for $〈{E}_{\ensuremath{\nu}}〉=50$ GeV, and $\frac{\ensuremath{\sigma}(\overline{\ensuremath{\nu}}n)}{\ensuremath{\sigma}(\overline{\ensuremath{\nu}}p)}=0.51\ifmmode\pm\else\textpm\fi{}0.16$ for $〈{E}_{\overline{\ensuremath{\nu}}}〉=40$ GeV. Bjorken-$x$ distributions for neutron and proton targets show that the majority quark in the nucleon has a broader momentum distribution in the infinite momentum frame than does the minority quark.