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arXiv · hep-ph/9907567

Angular Dependence of the Nuclear Enhancement of Drell-Yan Pairs

R. J. Fries·B. Müller·A. Schäfer·E. Stein
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Abstract

We calculate the nuclear enhancement in the angular distribution of Drell-Yan pairs produced in proton-nucleus reactions. Nuclear effects are encoded in universal twist-4 parton correlation functions. We find that the Lam-Tung relation for the angular coefficients of the lepton-pair distribution holds for the double-hard, but not for the soft-hard contribution. We also predict that nuclear enhancement effects at RHIC energies can be large.

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R. J. Fries, B. Müller, A. Schäfer, E. Stein. 1999-10-09. Angular Dependence of the Nuclear Enhancement of Drell-Yan Pairs. https://doi.org/10.1103/physrevlett.83.4261

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