Use of transverse beam polarization to probe anomalous VVH interactions at a Linear Collider

TL;DR

This paper explores how transverse beam polarization at the ILC can enhance the detection and discrimination of anomalous VVH interactions, especially in probing CP-odd and CP-even ZZH couplings with improved sensitivity.

Contribution

It introduces a novel approach using transverse polarization to separately probe and distinguish all components of the general ZZH vertex, including CP-odd and CP-even terms.

Findings

Transverse polarization improves sensitivity to CP-odd ZZH couplings.

It enables discrimination between different CP-even ZZH terms.

Combining polarization methods provides comprehensive probing of VVH interactions.

Abstract

We investigate use of transverse beam polarization in probing anomalous coupling of a Higgs boson to a pair of vector bosons, at the International Linear Collider (ILC). We consider the most general form of VVH (V = W/Z) vertex consistent with Lorentz invariance and investigate its effects on the process e+ e- --> f bar{f} H, f being a light fermion. Constructing observables with definite CP and naive time reversal (tilde T) transformation properties, we find that transverse beam polarization helps us to improve on the sensitivity of one part of the anomalous ZZH coupling that is odd under CP. Even more importantly it provides the possibility of discriminating from each other, two terms in the general ZZH vertex, both of which are even under CP and tilde T. Use of transverse beam polarization when combined with information from unpolarized and linearly polarized beams therefore, allows one to have completely independent probes of all the different parts of a general ZZH vertex.