Precise correction to parameter ρ in the littlest Higgs model

In this paper tree-level violation of weak isospin parameter, ρ in the frame of the littlest Higgs model is studied. The potentially large deviation from the standard model prediction for the ρ in terms of the littlest Higgs model parameters is calculated. The maximum value for ρ for f=1TeV, c=0.05,c′= 0.05 and υ′= 1.5GeV is ρ=1.2973 which means a large enhancement than the SM.