Testing nonrelativistic QCD factorization in charmonium production

by Bernd Kniehl (Desy)

Monday 14 Jun 2010, 14:15 → 15:45 Europe/Berlin

Seminar room 3344 (TUM - Physics Department - Garching)

The factorization formalism of nonrelativistic QCD (NRQCD) provides a rigorous theoretical framework for the description of heavy-quarkonium production and decay, predicting the existence of color-octet processes in nature. Unfortunately, the experimental verification of the predicted universality of the NRQCD long-distance matrix elements is hampered by the lack of next-to-leading-order (NLO) predictions. We review this deadlocked situation and take a first step towards its solution by calculating the cross section of J/psi photoproduction at NLO and comparing it with recently published data from DESY HERA.