A fresh look at diffractive J/ψ photoproduction at HERA, with predictions for THERA
نویسنده
چکیده
We quantify perturbative and non-perturbative QCD effects in the exclusive J/ψ-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.
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S ep 2 00 0 A fresh look at diffractive J / ψ photoproduction at HERA , with predictions for THERA
A fresh look at diffractive J/ψ photoproduction at HERA, with predictions for THERA. Abstract A new analysis of the photoproduction of the J/ψ-family is presented incorporating our recent model for the dipole cross section. The relative contributions from small and large transverse size fluctuations of the photon are clear and explicitly illustrate the mixing of pertur-bative and non-perturbati...
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