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Ratios of inclusive electron-nucleus cross sections are studied at incoming electron energies of 1 GeV to 25 GeV and (Bjorken) variable [ital x][sub [ital B][ital j]][gt]1 where many of the present theoretical speculations and the available and forthcoming experimental data are focused on. An alternative analysis which accounts for nuclear target mass effects is proposed.

We present a new derivation of the convolution formula for the contributions of nuclear binding to the structure functions measured in the deep inelastic scattering of leptons from nuclei. The derivation, which is manifestly covariant, gives a new binding correction. This new correction, which depends on the mass of the recoiling nucleon fragments, gives corrections that are numerically significant, and that improve the agreement between theory and experiment at large x. We conclude that nuclear binding effects may be sufficient to explain the European-Muon-Collaboration effect at large x.

It is shown that if the effects of nucleon binding on deep inelastic scattering are considered within many-body realistic descriptions of nuclei which include nucleon-nucleon correlations, the European-Muon-Collaboration effect in light and medium weight nuclei and nuclear matter can be accounted for in the region 0.2{le}{ital x}{le}0.5, but a systematic discrepancy between theory and experiment remains to be explained for 0.5{le}{ital x}{le}0.9.

The contribution of the nucleonic component to deep inelastic lepton scattering off {sup 2}H, {sup 3}H, {sup 3}He, and {sup 4}He nuclei is analyzed in terms of momentum distributions and spectral functions obtained from few-body calculations which employ realistic nucleon-nucleon interactions. The nuclear structure function is evaluated within the framework of the convolution model taking relativistic effects into account by means of the flux factor. A comparison with previous calculations performed with a nonrelativistic normalization of the spectral function and using, in the case of {sup 4}He, an independent particle model, is presented. It is shown that short-range and tensor correlations resulting from realistic nucleon-nucleon interactions strongly increase the nucleon mean removal and kinetic energies and, consequently, enhance the calculated European Muon Collaboration effect in the direction suggested by the experimental data in the region 0.2{le}{ital x}{le}0.7; for {ital x}{le}0.2 and {ital x}{ge}0.7, an appreciable discrepancy between theory and experiment still persists and the difficulties in giving an interpretation of the effect in the whole range of {ital x}, in terms of nucleonic degrees of freedom only, are pointed out. The role of {ital Q}{sup 2} rescaling is analyzed; it is found that present experimental data seem to require onlymore » a small increase of the quark confinement size for a nucleon imbedded in the nuclear medium. The nuclear structure function for three-nucleon systems is calculated in the region {ital x}{gt}1, where it is shown to be very sensitive to the correlation structure of the nucleon spectral function.« less

We present a comprehensive analysis of deep inelastic scattering from He-3 and H-3, focusing in particular on the extraction of the free neutron structure function, F_2^n. Nuclear corrections are shown to cancel to within 1-2% for the isospin-weighted ratio of He-3 to H-3 structure functions, which leads to more than an order of magnitude improvement in the current uncertainty on the neutron to proton ratio F_2^n/F_2^p at large x. Theoretical uncertainties originating from the nuclear wave function, including possible non-nucleonic components, are evaluated. Measurement of the He-3 and H-3 structure functions will, in addition, determine the magnitude of the EMC effect in all A < 4 nuclei., 40 pages, 12 figures, to appear in Phys. Rev. C