Measurement of $\bar��_��$ and $��_��$ charged current inclusive cross sections and their ratio with the T2K off-axis near detector

We report a measurement of cross section $��(��_��+{\rm nucleus}\rightarrow��^{-}+X)$ and the first measurements of the cross section $��(\bar��_��+{\rm nucleus}\rightarrow��^{+}+X)$ and their ratio $R(\frac{��(\bar ��)}{��(��)})$ at (anti-)neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K $\bar��/��$-flux, for the detector target material (mainly Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory frame kinematics of $��_��$500 MeV/c. The results are $��(\bar��)=\left( 0.900\pm0.029{\rm (stat.)}\pm0.088{\rm (syst.)}\right)\times10^{-39}$ and $��(��)=\left( 2.41\ \pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}$ in units of cm$^{2}$/nucleon and $R\left(\frac{��(\bar��)}{��(��)}\right)= 0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.
18 pages, 8 figures