Abstract
Charmonium production from the hadron gas formed in ultra-relativistic heavy-ion collisions is studied. Using the
J/ψ
-hadron absorption cross section determined from the nonperturbative quark-exchange model, which has a peak value similar to that used in the comover model for
J/ψ
suppression and a thermally averaged value consistent from that extracted from
J/ψ
data in heavy-ion collisions, we find that
J/ψ
production from the hadron gas is negligible in heavy-ion collisions at RHIC energies but is important at LHC energies as a result of the large number of charm mesons produced at higher energy collisions. The number of
J/ψ
produced from these secondary collisions at LHC may be comparable to that of primary
J/ψ
's, which are expected to be dissociated in the quark-gluon plasma created in the collisions, leading thus to a possible absence of
J/ψ
suppression. Similar results are obtained for
ψ
′
production in ultra-relativistic heavy-ion collisions.