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arXiv · 1907.06471

Towards a determination of the low $x$ gluon via exclusive $J/ψ$ production

Chris A. Flett·Stephen P. Jones·Alan D. Martin·Misha G. Ryskin·Thomas Teubner
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Abstract

We discuss how the stability of the theoretical prediction for exclusive $J/ψ$ photoproduction has been improved through a systematic taming of the known $\overline{\text{MS}}$ coefficient functions by accounting for a formally power suppressed, but numerically significant, correction encoded within a $Q_0$ cut. The phenomenological implications of this will be emphasised meaning, ultimately, the possibility to include the exclusive data into a global fitter framework to provide constraints on the small $x$ gluon.

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Chris A. Flett, Stephen P. Jones, Alan D. Martin, Misha G. Ryskin, Thomas Teubner. 2019-07-15. Towards a determination of the low $x$ gluon via exclusive $J/ψ$ production. https://arxiv.org/abs/1907.06471

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