Charmonium production at the LHC

The analyses of large transverse momentum charmonium production at the Tevatron have shown that fragmentation of gluons is an important production mechanism. We study large-p_T charmonium production in pp collisions at the LHC, and find that due to the copious gluon production at this energy, the gluon fragmentation contribution completely overwhelms the fusion contribution and the charm quark fragmentation contribution. Our analysis shows that for J/\psi production at the LHC, there is a significant event rate even for p_T \sim~100~GeV. The measurement of the cross-section at such large values of p_T will provide a very important test of the fragmentation mechanism