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The effect of gluon depletion on J/psi suppression in pA and AA collisions

Rudolph C. Hwa·Jan Pisut·Neva Pisutova
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Abstract

The enhanced suppression of $J/ψ$ production at large $x_F$ in $pA$ collisions is studied in the framework of gluon depletion at large $x_1$. The nonperturbative process that modifies the gluon distribution as the gluons propagate in nuclear matter is described by an evolution equation with a kernal to be determined by phenomenology. With nuclear shadowing and anti-shadowing taken into account, the effect on the gluon distribution is shown to be a depletion in excess of 40% at $x_1 \approx 0.8$ for $A > 100$. There is a small amount of enhancement of the gluon distribution at small $x_1$, but it does not lead to any contradiction with the existing data on $J/ψ$ suppression in the central region. Extentions to $ψ^{\prime}$ suppression and $AB$ collisions are also investigated in the framework of gluon redistribution.

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Rudolph C. Hwa, Jan Pisut, Neva Pisutova. 2001-03-09. The effect of gluon depletion on J/psi suppression in pA and AA collisions. https://doi.org/10.1103/physrevc.64.054611

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