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

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.

25 pages, 14 figures, 8 tables. Extended PDF analysis to include ABM11 5flv nlo. Added summary plots of LHCb cross-sections. Include shift of gluon PDF central value for CT10, NNPDF sets assuming different pseudodata values. Matches version to be published in JHEP

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Cited by in corpus (14)

• Parton distributions for the LHC Run II
• The PDF4LHC report on PDFs and LHC data: Results from Run I and preparation for Run II
• PDF reweighting in the Hessian matrix approach
• First observation of top quark production in the forward region
• Single top-quark production at the Tevatron and the LHC
• Measurement of forward top pair production in the dilepton channel in $pp$ collisions at $\sqrt{s}=13$ TeV
• Measurement of forward $t\overline{t}$, $W+b\overline{b}$ and $W+c\overline{c}$ production in $pp$ collisions at $\sqrt{s}=8$ TeV
• Leptonic top-quark asymmetry predictions at LHCb
• The leptonic $W^{\pm }$ boson asymmetry in association with jets at LHCb, and PDF constraints at large-$x$
• Resummation for rapidity distributions in top-quark pair production
• Asymmetric heavy-quark hadroproduction at LHCb: Predictions and applications
• Understanding forward $B$ hadron production
• Summary of the Topical Workshop on Top Quark Differential Distributions 2014
• Measurement of the top-quark production cross-section and charge asymmetry at LHCb