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arXiv · 1311.1810

Feasibility of top quark measurements at LHCb and constraints on the large-$x$ gluon PDF

Rhorry Gauld
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Abstract

The forward LHCb acceptance opens interesting possibilities of studying precision Standard Model hard processes in a kinematical region beyond the reach of ATLAS and CMS. In this paper we perform a feasibility study for cross-section measurements of top quark pairs with the LHCb detector, with an analysis of signal and background rates for selected final states, and determine the potential precision achievable at $\sqrt{s} =$ 7 and 14~TeV. We then study the dependence of theoretical uncertainties on the pseudorapidity distribution of top quarks produced in pair production at NLO, and observe that a cross-section measurement at high pseudorapidity has enhanced sensitivity to probe the high-$x$ gluon PDF as compared to measurements in the central-region. Based on simulated pseudodata, the impact of a 14~TeV cross-section measurement on the gluon PDF and charge asymmetry is quantified.

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Rhorry Gauld. 2014-03-06. Feasibility of top quark measurements at LHCb and constraints on the large-$x$ gluon PDF. https://doi.org/10.1007/jhep02(2014)126

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