Holographic Approaches to DIS on a Nucleus

We consider deep inelastic scattering (DIS) on a dense nucleus described as an extremal RN-AdS black hole with holographic quantum fermions in the bulk. We find that the R-ratio (the ratio of the structure function of the black hole to proton) exhibit shadowing for x < 0.1, anti-shadowing for 0.1 < x < 0.3, EMC-like effect for 0.3 < x < 0.8 and Fermi motion for x > 0.8 in a qualitative agreement with the experimental observation of the ratio for DIS on nucleus for all range of x. We also take the dilute limit of the black hole and show that its R-ratio exhibits EMC-like effect for 0.2 < x < 0.8 and the Fermi motion for x > 0.8, and no shadowing is observed in the dilute limit for both bottom-up (using Thomas-Fermi approximation for the nucleon distribution inside the dilute nucleus), and top-down (considering the dilute nucleus to be a Fermi gas in AdS) approaches.