$J/Ψ$ and $Ψ'$ Suppression in Heavy Ion Collisions
We study the combined effect of nuclear absorption and final state interaction with co-moving hadrons on the $J/Ψ$ and $Ψ'$ suppression in proton-nucleus and nucleus-nucleus collisions. We show that reasonable description of the experimental data can be achieved with theoretically meaningful values of the cross-sections involved and without introducing any dicontinuity in the $J/Ψ$ or $Ψ'$ survival probabilities.