psi (prime) and J/(psi) suppression in high-energy nucleon-nucleus and nucleus-nucleus collisions

摘要

The observed features of (psi)' to J/(psi) 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 c(bar c) systems with baryons at high relative energies, the absorption cross sections are insensitive to the radii of the c(bar c) systems, as described by the Additive Quark Model. For the soft component due to the low energy c(bar c) interactions with soft particles produced by other baryon-baryon collisions, the absorption cross sections are greater for (psi)' than for J/(psi), because the breakup threshold for (psi)' is much smaller than for (psi).