Exploiting the WH/ZH symmetry in the search for New Physics

TL;DR

This paper proposes a method to isolate the gluon-initiated $ZH$ production component by comparing $ZH$ and $WH$ processes, enabling high-precision tests for New Physics at the HL-LHC.

Contribution

It introduces a novel approach to probe the $gg\to ZH$ process by leveraging the similarity to $WH$ production and predicting their cross-section ratio with high accuracy.

Findings

The cross-section ratio $ZH/WH$ can be predicted precisely.

BSM scenarios can significantly affect the $gg\to ZH$ component.

The method enhances sensitivity to New Physics in $ZH$ production.

Abstract

We suggest to isolate the loop-induced gluon-initiated component ($gg\to ZH$) for associated $ZH$ production by using the similarity of the Drell-Yan-like component for $ZH$ production to the $WH$ process. We argue that the cross-section ratio of the latter two processes can be predicted with high theoretical accuracy. Comparing it to the experimental $ZH/WH$ cross-section ratio should allow to probe for New Physics in the $gg\to ZH$ component at the HL-LHC. We consider typical BSM scenarios in order to exemplify the effect they would have on the proposed observable.