Abstract
Nuclear shadowing corrections to the structure functions of deep inelastic scattering on intermediate-mass nuclei are calculated at very small values of Bjorken x and small values of Q^2 (Q^2<5 Gev^2). The two-component approach developed in previous works of authors for a description of the nucleon structure functions of deep inelastic scattering is used. It is shown that the hard component of the nucleon structure functions that arises, in terms of the colour dipole model, from qq-pairs with a high transverse momentum, is almost not shadowed. It is shown that a change of the slope of the shadowing curve with a decrease of x depends, at small values of x, on the relative contribution of the hard component to the nucleon structure function (this contribution is a function of x and Q^2) and on a size of gluon saturation effects. It is shown that an accounting for saturation effects becomes essential for predictions of shadowing at x<10^-4, depending on a value of Q^2. Results of numerical calculations of nuclear shadowing for several nuclei are compared with available data of the E665 and the NMC collaborations.
Highlights
It is well known that at small values of Bjorken x (x ≤ 0.1 for Q2 ≥ 1 GeV2), the inclusive structure function of deep inelastic scattering (DIS) on a nucleus with A nucleons is smaller than the incoherent sum of the nucleon structure functions, i.e., F2A < AF2N
The photoabsorption cross section σγÃN contains the generalized vector dominance (GVD) part and the perturbative term taking into account a contribution of those hadronic fluctuations of the virtual photon whose interactions with the target nucleon are described by perturbative QCD
In the color dipole picture, to a reducing of the phase space of qqpairs produced by the virtual photon and provides the approximate Q scaling, Q2σγÃN ∼ const: qqpairs with a small transverse momentum have a large transverse size and interact with the target nucleon with a large cross section, and, just by this reason, we may assume that σVnN in Eq (10) does not depend on the meson mass
Summary
It is well known that at small values of Bjorken x (x ≤ 0.1 for Q2 ≥ 1 GeV2), the inclusive structure function of deep inelastic scattering (DIS) on a nucleus with A nucleons is smaller than the incoherent sum of the nucleon structure functions, i.e., F2A < AF2N. In GVD, excited states of light vector mesons (ρ0; ρ00; ...) are included in the mass spectrum of the hadronic fluctuations of the virtual photon [11,13] In such an approach, the photoabsorption cross section σγÃN contains the GVD (i.e., nonperturbative) part and the perturbative term taking into account a contribution of those hadronic fluctuations of the virtual photon whose interactions with the target nucleon are described by perturbative QCD. The photoabsorption cross section σγÃN contains the GVD (i.e., nonperturbative) part and the perturbative term taking into account a contribution of those hadronic fluctuations of the virtual photon whose interactions with the target nucleon are described by perturbative QCD Just this approach is used for calculations of the DIS structure functions in [24,25,26].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
