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arXiv · 1212.5344

Massive neutral gauge boson production as a probe of nuclear modifications of parton distributions at the LHC

Abstract

We analyze the role of nuclear modifications of parton distributions, notably, the nuclear shadowing and antishadowing corrections, in production of lepton pairs from decays of neutral electroweak gauge bosons in proton-lead and lead-collisions at the LHC. Using the Collins-Soper-Sterman resummation formalism that we extended to the case of nuclear parton distributions, we observed a direct correlation between the predicted behavior of the transverse momentum and rapidity distributions of the produced vector bosons and the pattern of quark and gluon nuclear modifications. This makes Drell-Yan pair production in $pA$ and $AA$ collisions at the LHC a useful tool for constraining nuclear PDFs in the small-$x$ shadowing and moderate-$x$ antishadowing regions.

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Vadim Guzey, Marco Guzzi, Pavel M. Nadolsky, Mark Strikman, Bowen Wang. 2012-12-21. Massive neutral gauge boson production as a probe of nuclear modifications of parton distributions at the LHC. https://doi.org/10.1140/epja%2Fi2013-13035-6

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