Conveners
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- LINGFENG LI (UC Davis)
Heavy new physics above LHC energies is best searched for through indirect effects in precise observables. In this talk I discuss our global analysis of top-quark observables in the framework of Standard Model Effective Field Theory. I show how to penetrate untrodden directions in the Wilson coefficient space by exploiting kinematic distributions and by measuring new observables in collected LHC data.
We present a new calculation of single-top-quark production at NNLO. Our calculation is fully differential in the five-flavor scheme and includes the full leptonic top-quark decay. Our results settle the issue of previous calculations that found disagreement at the level of the NNLO corrections. We discuss the relevance of the process and the higher-order corrections for Standard Model...
We propose to utilize the polarization information of the $Z$ bosons in $ZZ$ production, via the gluon-gluon fusion process $gg\to ZZ$, to probe the $Zt\bar{t}$ gauge coupling. The contribution of longitudinally polarized $Z$ bosons is sensitive to the axial-vector component ($a_t$) of the $Zt\bar{t}$ coupling. We demonstrate that the angular distribution of the charged lepton from $Z$ boson...
Due to its high mass top quarks decay before top-flavoured hadrons are formed. This feature leads to interesting phenomenological consequences, among them is the access to spin polarisation effects in top-quark production. While top-quarks are produced unpolarized in top-quark-antiquark pair production, there exists a correlation between the spins of the top-quark and the top-antiquark. In the...
The top quark is the heaviest elementary particle in Standard Model. Measurements involving top quarks in their final states provide precision tests of the Standard Model and are also sensitive to new physics at the high-energy frontier. The latest cross-section measurements of rare processes with top quarks (tZq, ttX, 4top production) are presented here using 13 TeV proton-proton collisions...
A comprehensive set of measurements of top quark pair and single top quark production in association with EWK bosons (W, Z or ɣ) is presented. The results are compared to theory predictions and re-interpreted as searches for new physics inducing deviations from the standard model predictions using an effective field theory approach. The status of the search for four top quark production, to...
Measurements of top quark properties using data collected by the CMS experiment are presented. Among them, the latest results on top mass and its running, top Yukawa coupling, the top sector of the CKM matrix, ttbar forward backward asymmetry, as well as other new results will be discussed.
Latest results on inclusive and differential top quark pair and single top quark production cross sections are presented using collision data collected by CMS. In different kinematic regimes, the differential cross sections are measured as a function of various observables of the top quarks and the jets and leptons of the event final state. The results are confronted with precise theory...
