Charmonium production via fragmentation at DESY HERA

Journal Article · Sat Nov 01 04:00:00 EST 1997 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.56.5820· OSTI ID:543909

Kniehl, B A ^[1]; Kramer, G ^[2]

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1. Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Munich (Germany)
2. II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)

The cross section for the photoproduction of large-p{sub T} J/{psi} mesons at DESY HERA is calculated at next-to-leading order, adopting a perturbative approach to describe the fragmentation of charm quarks and gluons into J/{psi} mesons. We treat the charm quark according to the massless factorization scheme, where it is assumed to be one of the active flavors inside the proton and the resolved photon. We present inclusive distributions in transverse momentum and rapidity, including the contributions due to direct and resolved photons. The importance of the color-octet components of the J/{psi} wave function, which contribute to the fragmentation process, is emphasized. In addition to prompt J/{psi} production, we consider also the production of {chi}{sub cJ} states followed by radiative decays to J/{psi} mesons, both in the color-singlet and color-octet channels. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 543909
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 9 Vol. 56; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
C QUARKS
CHARMONIUM
COLOR
CROSS SECTIONS
FACTORIZATION
FLAVOR
FRAGMENTATION
GLUONS
J PSI-3097 MESONS
OCTET MODEL
PERTURBATION THEORY
PHOTON-PROTON INTERACTIONS
PHOTONS
PHOTOPRODUCTION
TRANSVERSE MOMENTUM
WAVE FUNCTIONS