  Charge-current quasielastic (CCQE) (anti)neutrino scattering cross sections
on a $^{12}$C target are analyzed using a spectral function $S(p,{\cal E})$
that gives a scaling function in accordance with the ($e,e'$) scattering data.
The spectral function accounts for the nucleon-nucleon (NN) correlations, it
has a realistic energy dependence and natural orbitals (NO's) from the Jastrow
correlation method are used in its construction. In all calculations the
standard value of the axial mass $M_A= 1.032$ GeV/c$^2$ is used. The results
are compared with those when NN correlations are not included, as in the
Relativistic Fermi Gas (RFG) model, or when harmonic-oscillator (HO)
single-particle wave functions are used instead of NO's. The role of the
final-state interactions (FSI) on the theoretical spectral and scaling
functions, as well as on the cross sections is accounted for. A comparison of
the results for the cases with and without FSI, as well as to results from the
phenomenological scaling function obtained from the superscaling analysis
(SuSA) is carried out. Our calculations based on the impulse approximation (IA)
underpredict the MiniBooNE data, but agree with the data from the NOMAD
experiment. The possible missing ingredients in the considered theoretical
models are discussed.
