Precision Measurements of Little Higgs Parameters at the International Linear Collider

We investigate the possibility of precision measurements for parameters of the littlest Higgs model with $T$ parity at the International Linear Collider. The model predicts new gauge bosons (${A}_{\mathrm{H}}$, ${Z}_{\mathrm{H}}$, and ${W}_{\mathrm{H}}$), among which the heavy photon (${A}_{\mathrm{H}}$) is a candidate for dark matter. The masses of these new gauge bosons strongly depend on the vacuum expectation value that breaks a global symmetry of the model. Through Monte Carlo simulations of the processes, ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{A}_{\mathrm{H}}{Z}_{\mathrm{H}}$ and ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{W}_{\mathrm{H}}^{+}{W}_{\mathrm{H}}^{\ensuremath{-}}$, we show how precisely the masses can be determined at the International Linear Collider for a representative parameter point of the model. We also discuss the determination of the little Higgs parameters and their impact on the future measurement of the thermal abundance of the dark matter relics in our Universe.