High Density QCD, Saturation and Diffractive DIS
  We review a consistent description of the fusion and saturation of partons in the Lorentz-contracted ultrarelativistic nuclei in terms of a nuclear attenuation of color dipole states of the photon and collective Weizs\"acker-Williams (WW) gluon structure function of a nucleus. Diffractive DIS provides a basis for the definition of the WW nuclear glue. The point that all observables for DIS off nuclei are uniquely calculable in terms of the nuclear WW glue amounts to a new form of factorization in the saturation regime. 
I.P. Ivanov (Institute of Mathematics, Novosibirsk), N.N. Nikolaev   (IKP, Forshcungszentrum Juelich and L.D.Landau Inst.), ...