Quarkonia production at fermilab

Summary

Recent data on J/ψ, ψ(2S),x _c and γ production has unraveled unexpected features of Q$\bar Q$ bound states production in high-energy hadronic collisions. In the 1992–1995 runs CDF has collected large samples of J/ψ, ψ(2S) and γ identified through their muonic decay. In the charmonium system all production sources have been separately measured and compared with the theoretical predictions. A large excess of direct production has been observed for both ψ(2S) and J/ψ. The relative production rate for thex _c has also been measured. Results on J/ψ, ψ(2S) andx _c production from the fixed-target experiments E789, E705 and E672/706 are also presented. Important features of the production of charmonium states are shared by fixed-target and collider data.