Hadronic scattering effects on ψ(2S) suppression in relativistic heavy-ion collisions

In this work we estimate the N ψ ( 2 S ) / N J / ψ yield ratio in heavy-ion collisions, considering the interactions of the ψ ( 2 S ) and J / ψ states with light mesons in the hadron gas formed at the late stages of these collisions. Starting from the appropriate effective Lagrangians, we first compute the thermally-averaged cross sections for the production and absorption of the mentioned states, and then use them as input in the rate equations to determine the time evolution of N ψ ( 2 S ) , N J / ψ and N ψ ( 2 S ) / N J / ψ . The main conclusion of our study is that the ψ ( 2 S ) and J / ψ multiplicities do not change much in the hadron gas phase and that the ψ ( 2 S ) is more absorbed than the J / ψ . The obtained final ratio is in agreement with recent experimental data.