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arXiv · 0806.3678

A look at the influence of the $J/ψ$ transverse momentum on shadowing

Andry M. Rakotozafindrabe
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Abstract

Stringent physical constraints relate the $J/ψ$ produced at a given transverse momentum $p_T$ to the Bjorken-$x$ of the initial gluons. We present a new approach which takes them into account in order to explicitely investigate the $p_T$-dependence of the shadowing effect on the $J/ψ$ production. Using the $J/ψ$ rapidity and $p_T$ spectra extracted from $\sqrt{s}=200\mathrm{GeV}$ p + p data from PHENIX, we build a Glauber Monte-Carlo code which includes shadowing in two alternative ways: multiple scattering corrections or $Q^2$ evolution of parton densities. We present our results in d + Au collisions at the same energy, notably providing the first prediction of the $J/ψ$ nuclear modification factor as a function of $p_T$, and compare them to the available data by adding some nuclear absorption effect.

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Andry M. Rakotozafindrabe. 2008-06-23. A look at the influence of the $J/ψ$ transverse momentum on shadowing. https://doi.org/10.1063/1.2987188

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