Underlying event measurement with ttbar+X events with p-p collision data at sqrt(s)=13 TeV

Measurements of the underlying event (UE) activity using charged particle properties in $t\overline{t}$ events in the $\mu$ + jets channel are presented. Proton-proton collision events at a center-of-mass energy of $\sqrt{s}=13$ TeV, corresponding to an integrated luminosity of 2.2 fb$^{-1}$ recorded by the CMS detector at the LHC, are used for the measurements. The measurements are found to be consistent with the predictions from the QCD Monte Carlo model generators used by CMS for the LHC Run II data.