2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49607Partons are defined as the quanta in a Fock space description of a hadron. Gluon saturation is described in the Weizsäcker-Williams approximation for a large nucleus. The elements of DGLAP and BFKL evolution are given with the BFKL equation derived in a large-$N_c$ dipole formalism. A more general discussion of saturation is given in terms of a dipole scattering on a nucleon or nucleus. Possible evidence for saturation at HERA is discussed.33 pages 15 figuresHigh Energy Physics - PhenomenologySmall-x Physics, High Parton Densities and Parton Saturation in QCDtext