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

31 August 2018

Abstract: Forward top quark pair production is studied in pp collisions in the μeb 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 Δ 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 Δ 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 σ t t ¯ = 126 ± 19 stat ± 16 syst ± 5 lumi f b ${\sigma}_{t\overline{t}}=126\pm 19\left(\mathrm{stat}\right)\pm 16\left(\mathrm{syst}\right)\pm 5\left(\mathrm{lumi}\right)\mathrm{f}\mathrm{b}$ 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.

Published in: JHEP 1808 (2018) 174