Measurement of the top quark mass with the ATLAS detector

Abstract

An overview is presented of the measurements of the top quark mass performed by the ATLAS experiment at the LHC with an integrated luminosity varying between 35 pb${}^{-1}$ and 4.7 fb${}^{-1}$. Different techniques are used to measure the top quark mass looking at events in all three signatures: fully-hadronic, lepton+jets and di-leptonic ones. The most precise measurement, using a template method on lepton+jets events, yields a top quark mass of 174.5 $\pm$ 0.6 (stat) $\pm$ 2.3 (syst) GeV. The dominant systematic uncertainties are related to the determination of the $b-$jet energy scale and the modelling of additional radiation accompanying the $t\bar{t}$ pair production.

Proceedings of the 36th International Conference on High Energy Physics (ICHEP), 4-11 July 2012, Melbourne, Australia