[en] The observed features of ψ' to J/ψ suppression in pA and nucleus-nucleus collisions can be explained in terms of a two-component absorption model. For the hard component of the absorption due to the interaction of the produced cc-bar systems with baryons at high relative energies, the absorption cross sections are insensitive to the radii of the cc-bar systems, as described by the Additive Quark Model. For the soft component due to the low energy cc-bar interactions with soft particles produced by other baryon-baryon collisions, the absorption cross sections are greater for ψ' than for J/ψ, because the breakup threshold for ψ' is much smaller than for ψ. (author)