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Prompt J/psi plus photon associated electroproduction at DESY HERA

Bernd A. Kniehl·Caesar P. Palisoc
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Abstract

We study the production of a prompt J/psi meson in association with a prompt photon in ep deep-inelastic scattering within the factorisation formalism of non-relativistic quantum chromodynamics (NRQCD) and demonstrate that this process provides a clean probe of the colour-octet mechanism at DESY HERA. Our analysis is based on an updated set of non-perturbative NRQCD matrix elements obtained through a joint fit to data on charmonium inclusive hadroproduction from runs I and II at the Fermilab Tevatron.

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Bernd A. Kniehl, Caesar P. Palisoc. 2006-08-22. Prompt J/psi plus photon associated electroproduction at DESY HERA. https://doi.org/10.1140/epjc%2Fs10052-006-0044-2

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