Fragmentation contributions to J/psi production at the Tevatron and the LHC

Abstract

We compute leading-power fragmentation corrections to $J/\psi$ production at the Tevatron and the LHC. We find that, when these corrections are combined with perturbative corrections through next-to-leading order in the strong coupling constant ${\alpha }_s$, we obtain a good fit to high-$p_T$ cross section data from the CDF and CMS Collaborations. The fitted long-distance matrix elements lead to predictions of near-zero $J/\psi$ polarization in the helicity frame at large $p_T$.

Comments: 5 pages, 4 figures, minor revisions, changes in notation, figures updated, version published in Physical Review Letters