Measurement of the charge asymmetry in top quark pair production with the CMS experiment

We present a measurement of the charge asymmetry in top quark pair production using an integrated luminosity of 36 pb$^{-1}$ collected during 2010 with the CMS detector. Top pair candidates with a signature of a charged lepton and at least four jets are selected. In order to measure the charge asymmetry in proton-proton collisions at a centre-of-mass energy of 7 TeV, the difference of absolute pseudo rapidities of top quark and anti-top quark $|\eta_{t}|-|\eta_{\bar t}|$ is used. The measured asymmetry $A_C=0.060\pm0.134{\rm (stat.)}\pm0.026{\rm (syst.)}$ is consistent with the asymmetry predicted by the Standard Model of $0.0130(11)$. The result is still dominated by the statistical uncertainty but it shows that CMS has the ability to measure this quantity.