We present measurements of ${\nu }_{\mu }$ charged-current cross section ratios on carbon, iron, and lead relative to a scintillator (CH) using the fine-grained MINERvA detector exposed to the NuMI neutrino beam at Fermilab. The measurements utilize events of energies $2<E_{\nu }<20\mathrm{GeV}$, with $⟨E_{\nu }⟩=8\mathrm{GeV}$, which have a reconstructed ${\mu }^{-}$ scattering angle less than 17° to extract ratios of inclusive total cross sections as a function of neutrino energy $E_{\nu }$ and flux-integrated differential cross sections with respect to the Bjorken scaling variable $x$. These results provide the first high-statistics direct measurements of nuclear effects in neutrino scattering using different targets in the same neutrino beam. Measured cross section ratios exhibit a relative depletion at low $x$ and enhancement at large $x$. Both become more pronounced as the nucleon number of the target nucleus increases. The data are not reproduced by GENIE, a conventional neutrino-nucleus scattering simulation, or by the alternative models for the nuclear dependence of inelastic scattering that are considered.

• Received 9 March 2014

DOI:https://doi.org/10.1103/PhysRevLett.112.231801