Unique Identification of Lee-Wick Gauge Bosons at Linear Colliders

TL;DR

This paper investigates whether Lee-Wick gauge bosons can be uniquely identified at linear colliders by analyzing specific scattering processes, addressing previous challenges faced at the LHC.

Contribution

It demonstrates that measurements at electron-positron colliders can distinguish Lee-Wick gauge bosons from other similar particles, solving a key identification problem.

Findings

Cross section measurements enable identification of LW gauge bosons.

Left-right polarization asymmetry helps distinguish LW states.

Unique identification possible at suitable collider energies.

Abstract

Grinstein, O'Connell and Wise have recently presented an extension of the Standard Model (SM), based on the ideas of Lee and Wick (LW), which demonstrates an interesting way to remove the quadratically divergent contributions to the Higgs mass induced by radiative corrections. This model predicts the existence of negative-norm copies of the usual SM fields at the TeV scale with ghost-like propagators and negative decay widths, but with otherwise SM-like couplings. In earlier work, it was demonstrated that the LW states in the gauge boson sector of these models, though easy to observe, cannot be uniquely identified as such at the LHC. In this paper, we address the issue of whether or not this problem can be resolved at an $e^+e^-$ collider with a suitable center of mass energy range. We find that measurements of the cross section and the left-right polarization asymmetry associated with Bhabha scattering can lead to a unique identification of the neutral electroweak gauge bosons of the Lee-Wick type.