The dominant production mechanism for heavy-quark–antiquark bound states with large transverse momentum is fragmentation, the splitting of a high energy parton into a quarkonium state and other partons. We show that the fragmentation functions D(z,μ) describing these processes can be calculated using perturbative QCD. We calculate the fragmentation functions for a gluon to split into S-wave quarkonium states to leading order in the QCD coupling constant.

• Received 30 November 1992

DOI:https://doi.org/10.1103/PhysRevLett.71.1673