J/ψ reaction mechanisms and suppression in the nuclear medium

Abstract

Recent studies of the interaction of vector mesons with nuclei make possible and opportune the study of the interaction of the J/ψ with nuclei and the investigation of the origin of the J/ψ suppression in its propagation thorough a nuclear medium. We observe that the transition of J/ψN to VN with V being a light vector, ρ,ω,φ, together with the inelastic channels, J/ψN→D̄Λc and J/ψN→D̄Σc, leads to a particular shape of the inelastic cross section. Analogously, we consider the mechanisms where the exchanged D collides with a nucleon and gives πΛc or πΣc. The cross section has a peak around √s=4415 MeV, where the J/ψN couples to a resonance predicted recently. We study the transparency ratio for electron-induced J/ψ production in nuclei at about 10 GeV and find that 30-35% of the J/ψ produced in heavy nuclei are absorbed inside the nucleus. This ratio is in line with depletions of J/ψ through matter observed in other reactions. © 2012 American Physical Society.