Hadronic production of heavy-quark bound states

Abstract

We consider the hadronic production of heavy-quark bound states ($Q\overline{Q}$) and also associated production of pairs of hadron containing heavy quarks ($\overline{Q}q+\overline{q}Q$). Calculations of total cross sections and of $x_F$ spectra are presented for both the $\frac{J}{\psi }$ and $\Upsilon$. Processes involving fusion of quarks as well as amalgamation of gluons from the beam and target hadrons are important but in both cases the production of $J^{\mathrm{PC}}=1^{--}$ bound states proceeds mainly via $P$-wave intermediate states. Processes involving gluons from the initial hadrons dominate at high energies for all beams and targets, and at all energies for proton and $K^{+}$ beams where quark fusion cannot proceed using only valence quarks.