Inclusive and differential cross-sections measurements in the single top tW e-mu channel with CMS

TL;DR

This paper reports measurements of inclusive and differential cross sections for single top quark production in association with a W boson in proton-proton collisions at 13 TeV, using events with one muon and one electron.

Contribution

It presents the first detailed differential cross-section measurements for tW production in the e-mu channel at 13 TeV, with unfolded results compared to NLO QCD predictions.

Findings

All measured distributions agree with theoretical predictions within uncertainties.

The analysis demonstrates the effectiveness of multivariate techniques in separating signal from background.

Results provide constraints for modeling single top quark production.

Abstract

Inclusive and normalised differential cross sections measurements are presented for the production of single top quarks in association with a W boson, in proton-proton collisions at a centre-of-mass energy of 13 TeV. Events containing one muon and one electron in the final state are analysed. For the inclusive measurement, a multivariate discriminant, exploiting the kinematic properties of the events, is used to separate the signal from the dominant t$\bar{\mathrm{t}}$ background. For the differential measurements, a fiducial region is defined according to the detector acceptance, and the requirement of exactly one b-tagged jet. The resulting distributions are unfolded to particle-level and compared with predictions at next-to-leading order in perturbative QCD. Within current uncertainties, all predictions agree with the data.