A fresh look at diffractive $J/\psi$ photoproduction at HERA, with predictions for THERA

Abstract

We quantify perturbative and non-perturbative QCD effects in the exclusive $J/\psi$-photoproduction cross section, and in the shrinkage of the differential cross section with respect to momentum transfer, $t$. We predict that in the high energy THERA region there will always be a significant contribution to this process that rises quickly with energy. This implies that the taming of the rise of the cross section with energy, due to both the expansion of spatially-small fluctuations in the photon and to higher twist effects, is rather gradual.

Published version, 29 pages, 16 figures, uses JHEP.cls. Substantially rewritten to better emphasize the generality of the results in response to the referee's comments. Predictions for MRST LO partons added, calculations and discussion of the real part of the amplitude and of alpha prime improved. Five of the original figures modified. Two new plots, of the dipole cross section for two different values of parameter lambda, and of energy dependence of alpha prime, added. Three additional references included

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Cited by in corpus (31)

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• 50 Years of Quantum Chromodynamics
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• Exclusive rho^0 production in deep inelastic scattering at HERA
• Two-gluon form factor of the nucleon and $J/\psi$ photoproduction
• Diffractive Photoproduction of Psi(2S) Mesons at HERA
• Exclusive J/ψ production in ultraperipheral collisions at the LHC: constrains on the gluon distributions in the proton and nuclei
• The Hadronic Final State at HERA
• Predictions for $e^{+}{e}^{-}\to J/\psi {\eta }_c$ with Light-Cone Wave-Functions
• Peripheral heavy ion collisions as a probe of the nuclear gluon distribution
• Measurement of exclusive ${\rm Y}$ photoproduction from protons in pPb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV
• A next-to-leading order QCD analysis of deeply virtual Compton scattering amplitudes
• Fading out of J/psi color transparency in high energy heavy ion peripheral collisions
• Nuclear shadowing in deep inelastic scattering on nuclei: leading twist versus eikonal approaches
• NRQCD Factorization for Twist-2 Light-Cone Wave-Functions of Charmonia
• Chiral dynamics and the growth of the nucleon's gluonic transverse size at small x
• Onset of Perturbative Color Opacity at Small x and Upsilon Coherent Photoproduction off heavy nuclei at LHC
• Heavy ions at the Future Circular Collider
• Deeply Virtual Compton Scattering and Saturation Approach
• Selected topics in diffraction with protons and nuclei: past, present, and future
• Investigating the Drell-Yan transverse momentum distribution in the color dipole approach
• Unitarity Corrections to the Drell-Yan Process in the Target Rest Frame
• Diffractive Photoproduction of Eta_c
• Using branching processes in nuclei to reveal dynamics of large-angle, two-body scattering
• Electron-Nucleus Collisions at THERA
• Exclusive Charmonium Production at the Electron-ion collider in China
• The Fermi motion contribution to J/ψproduction at the hadron colliders
• Soft Gluon Approach for Diffractive Photoproduction of J/psi
• The Black Body Limit in Deep Inelastic Scattering