Cargando…

Measurements of differential cross sections for $\mathrm{t \bar t}$ production in proton-proton collisions at $\sqrt{s}=13~\mathrm{TeV}$ using events containing two leptons

Measurements are presented of differential top quark pair ($\mathrm{t \bar t}$) production cross sections using events containing two leptons produced in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the CERN LHC in 2016 and correspond...

Descripción completa

Detalles Bibliográficos
Autor principal: CMS Collaboration
Publicado: 2018
Materias:
Acceso en línea:http://cds.cern.ch/record/2621975
Descripción
Sumario:Measurements are presented of differential top quark pair ($\mathrm{t \bar t}$) production cross sections using events containing two leptons produced in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the CERN LHC in 2016 and correspond to an integrated luminosity of $35.9~\mathrm{fb^{-1}}$. The differential cross sections are presented as functions of kinematic observables of the top quarks and their decay products, the $\mathrm{t \bar t}$ system, and the total number of jets in the event. The differential cross sections are defined both with particle-level objects in a fiducial phase space close to that of the detector acceptance and with parton-level top quarks in the full phase space. All results are compared with standard model predictions from Monte Carlo simulations with next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD) at matrix-element level interfaced to parton-shower simulations. Where possible, parton-level results are compared to calculations with beyond NLO precision in QCD. Significant disagreement is observed between data and predictions for numerous observables. The measurements are used to constrain the top quark chromomagnetic dipole moment in an effective field theory framework at NLO in QCD and to extract $\mathrm{t \bar t}$ and leptonic charge asymmetries.