(Non)thermal aspects of charmonium production and a new look at J/ ψ suppression

• Published in: Physics letters. B Vol. 490; no. 3; pp. 196 - 202
• Main Authors: Braun-Munzinger, P., Stachel, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-10-2000
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/S0370-2693(00)00991-6

To investigate a recent proposal that J/
ψ production in ultra-relativistic nuclear collisions is of thermal origin we have reanalyzed the data from the NA38/50 Collaboration within a thermal model including charm. Comparison of the calculated with measured yields demonstrates the non-thermal origin of hidden charm production at SPS energy. However, the ratio
ψ′/(J/
ψ) exhibits, in central nucleus-nucleus collisions, thermal features which lead us to a new interpretation of open charm and charmonium production at SPS energy. Implications for RHIC and LHC energy measurements will be discussed.