First Measurement of the Cross Section for Top-Quark Pair Production in Proton-Proton Collisions at sqrt(s)=7 TeV

TL;DR

This paper reports the first measurement of the top-quark pair production cross section in proton-proton collisions at 7 TeV using CMS data, with results consistent with theoretical predictions.

Contribution

It presents the inaugural measurement of the top-quark pair production cross section at 7 TeV at the LHC, using a specific final state and data-driven background estimation.

Findings

Measured cross section: 194 ± 72 (stat) ± 24 (syst) ± 21 (lumi) pb

Observed 11 events with an expected background of 2.1 ± 1.0 events

Results agree with next-to-leading order theoretical predictions.

Abstract

The first measurement of the cross section for top-quark pair production in pp collisions at the LHC at center-of-mass energy sqrt(s)= 7 TeV has been performed using 3.1 {\pm} 0.3 inverse pb of data recorded by the CMS detector. This result utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse energy, and two or more jets. Backgrounds from Drell-Yan and non-W/Z boson production are estimated from data. Eleven events are observed in the data with 2.1 {\pm} 1.0 events expected from background. The measured cross section is 194 {\pm} 72 (stat.) {\pm} 24 (syst.) {\pm} 21 (lumi.) pb, consistent with next-to-leading order predictions.