Signatures of Extra Gauge Bosons in the Littlest Higgs Model with T-parity at Future Colliders

Abstract

We study the collider signatures of a T-odd gauge boson $W_H$ pair production in the Littlest Higgs Model with T-parity (LHT) at Large Hadron Collider (LHC) and Linear Collider (LC). At the LHC, we search for the $W_H$ boson using its leptonic decay, i.e. $pp\to W_H^{+}{W}_H^{-}\to A_H{A}_H{\ell }^{+}{\nu }_{\ell }{\ell }^{\prime -}{\bar{\nu }}_{{\ell }^{\prime }}$, which gives rise to a collider signature of ${\ell }^{+}{\ell }^{\prime -}+\text{met}$. We demonstrate that the LHC not only has a great potential of discovering the $W_H$ boson in this channel, but also can probe enormous parameter space of the LHT. Due to four missing particles in the final state, one cannot reconstruct the mass of $W_H$ at the LHC. But such a mass measurement can be easily achieved at the LC in the process of $e^{+}{e}^{-}\to W_H^{+}{W}_H^{-}\to A_H{A}_H{W}^{+}{W}^{-}\to A_H{A}_{H}jjjj$. We present an algorithm of measuring the mass and spin of the $W_H$ boson at the LC. Furthermore, we illustrate that the spin correlation between the $W$ boson and its mother particle ($W_H$) can be used to distinguish the LHT from other new physics models.

Comments: version to appear in PRD (a few references added)