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arXiv · 0709.4406

Small x gluon from exclusive J/psi production

A. D. Martin·C. Nockles·M. Ryskin·T. Teubner
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Abstract

Exclusive J/psi production, gamma* p -> J/psi p, offers a unique opportunity to determine the gluon density of the proton in the small x domain. We use the available HERA data to determine the gluon distribution in the region 10^{-4} <~ x <~ 10^{-2} and 2 <~ Q^2 <~ 10 GeV^2, where the uncertainty on the gluon extracted from the global parton analyses is large. The gluon density is found to be approximately flat at the lower scale; it is compared with those of recent global analyses.

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A. D. Martin, C. Nockles, M. Ryskin, T. Teubner. 2007-09-27. Small x gluon from exclusive J/psi production. https://doi.org/10.1016/j.physletb.2008.02.067

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