Quarkonium production atpp¯colliders

We evaluate cross sections for η${(\mathrm{}}^1$ $S_0$) and ψ${(\mathrm{}}^3$ $S_1$) quarkonium states of cc¯, bb¯, and tt¯ from lowest-order gg→η,${\chi }_0$,2${(\mathrm{}}^3$ ${\mathrm{P}}_0$,2 ) and gg→ψg subprocesses, including ${\chi }_J$→ψγ decays. Data on pp production of ψ and Υ are well described. High rates are predicted for ${\eta }_b$ and ${{\rm Y}}_b$ production at pp¯ colliders. The much smaller η(tt¯) and ψ(tt¯) rates are critically dependent on the singular part of the confining potential.