Measurement of the inclusive $\mathrm{t\bar{t}}$ production cross section in proton-proton collisions at $\sqrt{s} =$ 5.02 TeV

TL;DR

This paper reports a measurement of the top quark pair production cross section at 5.02 TeV proton-proton collisions, combining data from different channels to improve accuracy and compare with Standard Model predictions.

Contribution

First measurement of the top quark pair production cross section at 5.02 TeV, combining multiple data sets to enhance precision and validate Standard Model predictions.

Findings

Measured cross section: 63.0 ± 4.1 (stat) ± 3.0 (syst+lumi) pb

Agreement with Standard Model prediction of 66.8 pb

Combined analysis reduces statistical uncertainty

Abstract

The top quark pair production cross section is measured in proton-proton collisions at a center-of-mass energy of 5.02 TeV. The data were collected in a special LHC low-energy and low-intensity run in 2017, and correspond to an integrated luminosity of 302 pb$^{-1}$. The measurement is performed using events with one electron and one muon of opposite charge, and at least two jets. The measured cross section is 60.7 $\pm$ 5.0 (stat) $\pm$ 2.8 (syst) $\pm$ 1.1 (lumi) pb. To reduce the statistical uncertainty, a combination with the result in the single lepton + jets channel, based on data collected in 2015 at the same center-of-mass energy and corresponding to an integrated luminosity of 27.4 pb$^{-1}$, is then performed. The resulting measured value is 63.0 $\pm$ 4.1 (stat) $\pm$ 3.0 (syst+lumi) pb, in agreement with the standard model prediction of 66.8 $^{+2.9}_{-3.1}$ pb.