Forward-Backward Charge Asymmetry in Z Production at the LHC

We present here a study on the determination of the effective weak mixing angle, ${\sin }^2{\theta }_{eff}^{lept}$ from the measurement of the Forward-Backward Asymmetry with a high a statistical precision, 10${}^{-4}$. To reach such a precision it is necessary to identify the electrons in the forward regions of the ATLAS detector. It is demonstrated that one can reach an electron-jet rejection of more than 100 with an efficiency on electron reconstruction better than 50%, by using a multivariate analysis.