Search for physics beyond the standard model in four and three top quark production events using proton-proton collisions at $\sqrt{s}$ = 13 TeV

Abstract

A search for physics beyond the standard model using four and three top quark production events is reported. The analyzed proton-proton collision data were recorded at 13 TeV with the CMS detector at the CERN LHC in 2016$-$2018 and correspond to an integrated luminosity of 138 fb$^{-1}$. Events with two same-sign, three, or four leptons (electrons and/or muons) are selected. Constraints on six Wilson coefficients that modify interactions between four third-generation quarks or between top quarks and the Higgs boson in the standard model effective field theory framework are derived. The data are further used to exclude narrow topphilic heavy resonances in the mass ranges between 400 GeV and 1.6 TeV depending on their spin and color states. Finally, the top quark Yukawa coupling is extracted, considering both $CP$-even and $CP$-odd contributions.