Double Higgs production at TeV Colliders in the Minimal Supersymmetric Standard Model

TL;DR

This work analyzes double Higgs production in the MSSM as a means to test trilinear Higgs self-couplings, focusing on the reference channels gg→hh at the LHC and e+e−→hhZ at a Linear Collider. It employs LO matrix elements for signal and background, includes one-loop and leading two-loop radiative corrections to Higgs masses and couplings via HDECAY, and studies tanβ=3 and 50 across MSSM parameters with m_A as a control, highlighting resonant H→hh enhancement when m_H>2m_h. The results indicate that, at the LHC, resonant production can yield observable signals and probe λ_Hhh for low tanβ, while at a Linear Collider the continuum rates are generally small, limiting access to triple-Higgs couplings. The analysis uses parton-level and fast detector-level simulations, lays out selection criteria for a four-b final state, and discusses irreducible QCD/EW backgrounds relevant to these channels.

Abstract

The reconstruction of the Higgs potential in the Minimal Supersymmetric Standard Model (MSSM) requires the measurement of the trilinear Higgs self-couplings. The `double Higgs production' subgroup has been investigating the possibility of detecting signatures of processes carrying a dependence on these vertices at the Large Hadron Collider (LHC) and future Linear Colliders (LCs). As reference reactions, we have chosen $gg\to hh$ and $e^+e^-\to h h Z$, respectively, where $h$ is the lightest of the MSSM Higgs bosons. In both cases, the $Hhh$ interaction is involved. For $m_H>2m_h$, the two reactions are resonant in the $H\to hh$ mode, providing cross sections which are detectable at both accelerators and strongly sensitive to the strength of the trilinear coupling involved. We explore this mass regime of the MSSM in the $h\to b\bar b$ decay channel, also accounting for irreducible background effects.

Figures (2)

• Figure 1: Diagrams contributing to $gg\to hh$ (top) and $e^+e^-\to hhZ$ (bottom) in the MSSM.
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