Energy evolution of the overlap functions: increasing ratio of σ_el(s)/σ_tot(s) and black ring emergence

Abstract We analyse the two possible options of the energy dependency of the elastic and inelastic overlap functions. These correspond to saturation of the black disk limit (BEL effect) and to the unitarity saturation (REL effect) at s → ∞. Relation of the REL effect to increase of the ratio σel(s)/σtot(s) and emergence of black ring picture at the LHC is underlined. Keywords: Central collisions; Elastic scattering; Unitarity.