Precise top mass determination using lepton distribution at LHC

Abstract: We present a new method to measure a theoretically well-defined mass of the top quark at the LHC. This method uses lepton energy distribution and has a boost-invariant nature. We perform a simulation analysis of the top mass reconstruction with this method for tt -> lepton+jets channel at the leading order. We estimate several major uncertainties in the top mass determination and find that they are under good control.