Mott Effect and J/Psi Dissociation at the Quark-Hadron Phase Transition

Abstract

We investigate the in-medium modification of pseudoscalar and vector mesons in a QCD motivated chiral quark model by solving the Dyson-Schwinger equations for quarks and mesons at finite temperature for a wide mass range of meson masses, from light (pi, rho) to open-charm (D, D*) states. At the chiral / deconfinement phase transition, the quark-antiquark bound states enter the continuum of unbound states and become broad resonances (the hadronic Mott effect). We calculate the in-medium cross sections for charmonium dissociation due to collisions with light hadrons in a chiral Lagrangian approach, and show that the D and D* meson spectral broadening lowers the threshold for charmonium dissociation by pi and rho meson impact. This leads to a step-like enhancement in the reaction rate. We suggest that this mechanism for enhanced charmonium dissociation may be the physical mechanism underlying the anomalous J/Psi suppression observed by NA50.

arXiv comment3 pages, 3 figures, uses EPJ style (included), contribution to the Proceedings of the International Conference on Quark Nuclear Physics, June 9 - 14, 2002, Juelich, Germany; 1 figure added, text added

References in corpus (6)

• (Non)Thermal Aspects of Charmonium Production and a New Look at J/$\psi$ Suppression
• Charmonium Suppression and Regeneration from SPS to RHIC
• Hadron correlators, spectral functions and thermal dilepton rates from lattice QCD
• Excess low energy photon pairs from pion annihilation at the chiral phase transition
• Mott effect at the chiral phase transition and anomalous J/Psi suppression
• Anomalous J/psi suppression and charmonium dissociation cross sections

Cited by in corpus (5)

• Heavy-Quark Diffusion in the Quark-Gluon Plasma
• Taming the Yukawa potential singularity: improved evaluation of bound states and resonance energies
• Strong Couplings of X(3872)_{J=1,2} and a New Look at J/psi Suppression in Heavy Ion Collisions
• Quarkonia and QGP studies
• Quantum mechanical model for J/psi suppression in the LHC era