Measurement of forward top pair production in the dilepton channel in $pp$ collisions at $\sqrt{s}=13$ TeV

TL;DR

This paper reports a measurement of top quark pair production in the forward region at 13 TeV using the LHCb detector, providing a precise cross-section compatible with Standard Model predictions.

Contribution

First measurement of forward top pair production in the dilepton channel at 13 TeV with LHCb, expanding the understanding of top quark production in this kinematic region.

Findings

Measured cross-section: 126 ± 19 (stat) ± 16 (syst) ± 5 (lumi) fb.

Results are consistent with Standard Model predictions.

Demonstrates LHCb's capability to study top quark physics.

Abstract

Forward top quark pair production is studied in $pp$ collisions in the $\mu eb$ final state using a data sample corresponding to an integrated luminosity of 1.93 fb$^{-1}$ collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The cross-section is measured in a fiducial region where both leptons have a transverse momentum greater than 20 GeV and a pseudorapidity between 2.0 and 4.5. The quadrature sum of the azimuthal separation and the difference in pseudorapidities, denoted $\Delta R$, between the two leptons must be larger than 0.1. The $b$-jet axis is required to be separated from both leptons by a $\Delta R$ of 0.5, and to have a transverse momentum in excess of 20 GeV and a pseudorapidity between 2.2 and 4.2. The cross-section is measured to be $$\sigma_{t\bar{t}}= 126\pm19\,(\mathrm{stat})\pm16\,(\mathrm{syst})\pm5\,(\mathrm{lumi})\,\,\mathrm{ fb}$$ where the first uncertainty is statistical, the second is systematic, and the third is due to the luminosity determination. The measurement is compatible with the Standard Model prediction.