Searches for new physics using the ttbar invariant mass distribution in pp collisions at sqrt(s)=8 TeV

TL;DR

This paper reports on searches for new physics in top quark-antiquark production using the ttbar invariant mass distribution in proton-proton collisions at 8 TeV, finding no deviations from the standard model and setting new limits.

Contribution

It introduces the first constraints on certain new physics models using ttbar invariant mass spectrum at 8 TeV LHC data.

Findings

Observed spectrum consistent with standard model

Set limits on new physics production cross sections

Probed previously unconstrained parameter space

Abstract

Searches for anomalous top quark-antiquark production are presented, based on pp collisions at sqrt(s) = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 inverse femtobarns, were collected with the CMS detector at the LHC. The observed ttbar invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements.