Measurement of the charge asymmetry in top quark pair production at 7 TeV

We present a measurement of the charge asymmetry in the semi-leptonic channel of the top quark pair events production using 36 $pb^{-1}$ of proton-proton collisions data at $\sqrt{s}=7$ TeV collected with CMS during 2010. The charge asymmetry $A_{C}$ was measured using the difference of absolute pseudo rapidities of top and anti-top quarks $\mid{\eta_{t}}\mid-\mid{\eta_{\bar{t}}}\mid$ and was found to be $A_{C}=0.060\pm0.134(\rm{stat.})\pm0.026(\rm{syst.})$. The result is dominated by the statistical uncertainty, but is consistent with the Standard Model prediction of $0.013\pm0.001$.