t-tbar Pair production cross section measurement at the LHC

TL;DR

This paper reports measurements of the top-antitop pair production cross sections at 7 TeV using ATLAS and CMS data, including various decay modes, jet multiplicities, and charge asymmetry, all consistent with the Standard Model.

Contribution

First comprehensive measurements of $t\bar{t}$ production cross sections, jet multiplicities, and charge asymmetry at the LHC with 7 TeV data, using multiple decay channels.

Findings

Measured inclusive cross sections in various decay modes.

Studied jet multiplicity to constrain initial state radiation.

Measured charge asymmetry consistent with Standard Model predictions.

Abstract

Measurement of $t\bar{t}$ pair production cross sections with an integrated luminosity of around 1 fb$^{-1}$ at $\sqrt{s}$ = 7 TeV obtained with the ATLAS and CMS detectors are reported. The inclusive cross sections in dilepton (ee, $e\mu$, $\mu\mu$ and $\mu\tau$), lepton+jets (e, $\mu$) and all hadronic decay modes are measured. In addition to inclusive cross section measurement, the study of jet multiplicity with additional jets are also presented, which is important to constrain the initial state radiation. Measurement of the charge asymmetry at the LHC is also presented. All measurements are compatible with Standard Model predictions.