Charged-current quasielastic (anti)neutrino cross sections on ¹²C with realistic spectral functions including meson-exchange contributions

A detailed study of charged current quasielastic (anti)neutrino scattering cross sections on a ¹²C target with no pions in the final state is presented. The initial nucleus is described by means of a realistic spectral function S(p;ε) in which nucleon-nucleon correlations are implemented by using natural orbitals through the Jastrow method. The roles played by these correlations and by final-state interactions are analyzed and discussed. The model also includes the contribution of weak two-body currents in the two-particle two-hole sector, evaluated within a fully relativistic Fermi gas. The theoretical predictions are compared with a large set of experimental data by the MiniBooNE, MINERνA and T2K experiments. Good agreement with experimental data is found over the whole range of neutrino energies. The results are also in global good agreement with the predictions of the super scaling approach, which is based on the analysis of electron-nucleus scattering data, with only a few differences seen at specific kinematics. (author)