Cargando…

Search for CP violating anomalous top quark coupling in pp collisions with the CMS detector at $\sqrt{s}=13~\mathrm{TeV}$

Results of a search for CP violation in top quark pair production are presented, using proton-proton collision data at a center-of-mass energy of $\sqrt{s}=13~\mathrm{TeV}$. The data set analyzed corresponds to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$ collected by the CMS experiment. Fina...

Descripción completa

Detalles Bibliográficos
Autor principal: CMS Collaboration
Publicado: 2020
Materias:
Acceso en línea:http://cds.cern.ch/record/2730231
Descripción
Sumario:Results of a search for CP violation in top quark pair production are presented, using proton-proton collision data at a center-of-mass energy of $\sqrt{s}=13~\mathrm{TeV}$. The data set analyzed corresponds to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$ collected by the CMS experiment. Final states with two charged leptons are considered. In this search two observables are probed, $\mathcal{O}_{1}$ and $\mathcal{O}_{3}$, which are the Levi-Civita tensors of the four-momenta of charged leptons, jets originating from $\text{b}$ quarks, and top quarks. Asymmetries in these observables are sensitive to CP violation, and their measurement is used to determine the chromoelectric dipole moment of the top quark. The chromoelectric dipole moments derived from the measured asymmetries in $\mathcal{O}_{1}$ and $\mathcal{O}_{3}$ are $ 0.58 \pm 0.69(\text{stat}) \pm 0.70 (\text{syst})$ $\times 10^{-18} g_{\text{S}} \cdot \rm{cm}$ and $-0.01 \pm 0.72(\text{stat}) \pm 0.58 (\text{syst})$ $\times 10^{-18} g_{\text{S}} \cdot \rm{cm}$, respectively, with $g_\text{S}$ the strong coupling. These results are consistent with the standard model prediction.