Boosting invisible searches via $\mathbf{ZH}$: From the Higgs Boson to Dark Matter Simplified Models

Abstract

Higgs boson production in association with a $Z$-boson at the LHC is analysed, both in the Standard Model and in Simplified Model extensions for Dark Matter. We focus on $H\to$invisibles searches and show that loop-induced components for both the signal and background present phenomenologically relevant contributions to the $\mathcal{B}\mathcal{R}(H\to \text{inv})$ limits. In addition, the constraining power of this channel to Simplified Models for Dark Matter with scalar and pseudo-scalar mediators $\varphi$ and $A$ is discussed and compared with non-collider constraints. We find that with $100f{b}^{-1}$ of LHC data, this channel provides competitive constraints to the non-collider bounds, for most of the parameter space we consider, bounding the universal Standard Model fermion-mediator strength at $g_v<1$ for moderate masses in the range of $100\text{GeV}<m_{\varphi /A}<400$ GeV.

Comments: 10 pages, 9 figures