Determination of littlest Higgs model parameters at the International Linear Collider

Abstract

We examine the effects of the extended gauge sector of the littlest Higgs model in high energy ${e}^{+}{e}^{\ensuremath{-}}$ collisions. We find that the search reach in ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}f\overline{f}$ at a $\sqrt{s}=500\text{ }\text{ }\mathrm{GeV}$ International Linear Collider covers essentially the entire parameter region where the littlest Higgs model is relevant to the gauge hierarchy problem. In addition, we show that this channel provides an accurate determination of the fundamental model parameters, to the precision of a few percent, provided that the CERN LHC measures the mass of the heavy neutral gauge field. Additionally, we show that the couplings of the extra gauge bosons to the light Higgs can be observed from the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}Zh$ for a significant region of the parameter space. This allows for confirmation of the structure of the cancellation of the Higgs mass quadratic divergence and would verify the little Higgs mechanism.