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arXiv · hep-ph/0409003

Probing small-$x$ gluons by low-mass Drell-Yan pairs at colliders

George Fai·Jianwei Qiu·Xiaofei Zhang
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Abstract

The transverse-momentum ($Q_T$) distribution of low-mass Drell-Yan pairs is calculated in QCD perturbation theory with all-order resummation of $α_s (α_s \ln(Q^2_T/Q^2))^n$ type terms. We demonstrate that the rapidity distribution of low-mass Drell-Yan pairs at large-enough transverse momentum is an advantageous source of constraints on the gluon distribution and its nuclear dependence. We argue that low-mass Drell-Yan pairs in the forward region provide a good and clean probe of small-$x$ gluons at collider energies.

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George Fai, Jianwei Qiu, Xiaofei Zhang. 2004-08-31. Probing small-$x$ gluons by low-mass Drell-Yan pairs at colliders. https://doi.org/10.1103/physrevc.71.014901

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