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arXiv · 1805.00842

Constraining PDFs from neutral current Drell-Yan measurements and effects of resummation in slepton pair production

Abstract

The high statistics that will be collected during the LHC Run-II (and beyond) open the path to precision measurements at the TeV scale, where the PDFs will play a crucial role in BSM searches. In the di-lepton final state accurate measurements of the Forward-Backward Asymmetry (AFB) will be available, particularly in the invariant mass region around the Z peak. We show that this observable displays a statistical error which is competitive with that assigned to the existing PDF sets and which will rapidly become smaller than the latter as the integrated luminosity grows, thereby offering a means of constraining the (anti)quark PDFs over a sizeable $(x,Q^2)$ range. In the context of SUSY searches we consider the effects of employing threshold-improved PDFs in a consistent calculation at NLO+NLL of slepton pair production cross sections. The calculations featuring a consistent resummation procedure both at PDF and partonic matrix element level are accompanied by PDF and scale uncertainties, and they provide a reliable and updated theoretical estimation for experimental data analyses at the LHC Run-II.

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Juri Fiaschi, Elena Accomando, Francesco Hautmann, Michael Klasen, Stefano Moretti. 2018-05-02. Constraining PDFs from neutral current Drell-Yan measurements and effects of resummation in slepton pair production. https://arxiv.org/abs/1805.00842

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