On relative contributions of fusion and fragmentation mechanisms in J/psi photoproduction at high energy

Abstract

We study J/psi photoproduction via the fusion and fragmentation mechanisms at the HERA Collider within the frameworks of the collinear parton model and the quasi-multi-Regge kinematics approach using the factorization formalism of non-relativistic QCD at leading order in the strong-coupling constant alpha_s and the relative velocity v of the bound quarks. It is shown that the fusion production mechanism dominates over the fragmentation production mechanism at the all relevant J/psi transverse momenta. The J/psi meson p_T-spectra in the fragmentation and fusion production at the asymptotically large p_T have equal slopes in the quasi-multi-Regge kinematics approach, oppocite the collinear parton model.

11 pages, 7 figures, revtex4

References in corpus (5)

• Measurement of the J/Psi Meson and b-Hadron Production Cross Sections in ppbar Collisions at sqrt s = 1960 GeV
• Feynman rules for effective Regge action
• Charmonium Production at High Energy in the k_T-Factorization Approach
• Measurement of inclusive differential cross sections for Upsilon(1S) production in p-pbar collisions at sqrt(s) = 1.96 TeV
• Bottomonium Production in the Regge Limit of QCD

Cited by in corpus (2)

• J/ψpolarization in photo-production up-to the next-to-leading order of QCD
• $\psi (2S)$ and ${\rm Y}(3S)$ hadroproduction in the parton Reggeization approach: Yield, polarization, and the role of fragmentation