The Relative $J/\Psi$ to ${\Psi }^{\prime }$ Suppression in Proton-Nucleus and Nucleus-Nucleus Collisions

Abstract

We calculate the nuclear suppression for $J/\Psi$ and ${\Psi }^{\prime }$ production within a coupled channel approach in the subspace of the $J/\Psi$ and ${\Psi }^{\prime }$ states. We are able to explain, why (i) the $J/\Psi$ and ${\Psi }^{\prime }$ show the same suppression from $200GeV$ to $800GeV$ in proton-nucleus collisions and why (ii) the ${\Psi }^{\prime }$ is absorbed more strongly than the $J/\Psi$ in nucleus-nucleus collisions at $200GeV$. The numerical result which includes only interactions with nucleons acconts for half of the observed suppression in sulphur-uranium collisions.

Comments: 8 pages, LATEX, 3 uuencoded figures