[Paper Review] Resonance Production of Three Neutral Supersymmetric Higgs Bosons at LHC

G. Cynolter, E. Lendvai+1 more|ArXiv.org|Mar 1, 2000

Particle physics theoretical and experimental studies8 citations

TL;DR

This paper investigates resonance-enhanced production of three lightest neutral supersymmetric Higgs bosons (hhh) via gluon fusion at the LHC within the MSSM. Using one-loop and leading two-loop corrections, it finds that trilinear Higgs couplings dominate the cross section—reaching up to 300 fb at tanβ=3—while quartic couplings are negligible due to suppressed contributions, making their measurement at LHC impossible.

ABSTRACT

Multiple production of Higgs particles is essential to study Higgs self-couplings at future high-energy colliders. In this paper we calculated the resonance contributions to the production of three lightest neutral supersymmetric Higgs bosons in gluon fusion at LHC. The cross sections due to trilinear Higgs couplings is sizeable but the measurement of the quartic coupling hhhH(h) seems to be impossible.

Motivation & Objective

• To study the resonance contributions to triple Higgs boson production (hhh) in gluon fusion at the LHC within the MSSM.
• To assess the feasibility of measuring trilinear and quartic Higgs self-couplings in the MSSM via this process.
• To determine the dominant Feynman diagrams and their contributions to the cross section, especially near resonance.
• To evaluate the impact of tanβ and MA on the production cross section and resonance enhancement.
• To conclude on the experimental observability of quartic Higgs couplings in the hhh final state at the LHC.

Proposed method

• Calculated cross sections for pp → hhh + X via gluon fusion using one-loop and leading two-loop radiative corrections to Higgs masses, widths, and couplings.
• Included triangle, box, and pentagon diagrams involving quark and squark loops, with pentagon graphs omitted for resonance analysis.
• Used Lorentz- and gauge-invariant tensor decomposition for helicity amplitudes (Sz=0 and Sz=2) to compute amplitudes.
• Employed the VEGAS integration package with GRV parton distribution functions for gluon luminosity at √s = 14 TeV.
• Modelled Higgs couplings using parameters MA (CP-odd Higgs mass), tanβ (ratio of VEVs), and α (Higgs mixing angle), with ε parameterizing top quark loop corrections.
• Computed resonance contributions via propagator poles: 1/(ŝ − MH² + iMHΓH), focusing on H → hh decay via λHhhh and λhhhh couplings.

Experimental results

Research questions

• RQ1 Can the resonance production of three lightest neutral Higgs bosons (hhh) be observed in gluon fusion at the LHC within the MSSM?
• RQ2 What is the relative contribution of trilinear versus quartic Higgs self-couplings to the hhh production cross section?
• RQ3 Is the quartic Higgs coupling λhhhh measurable in the hhh final state at the LHC?
• RQ4 How does the cross section depend on tanβ and MA, especially near resonance?
• RQ5 Why is the contribution from quartic coupling diagrams negligible despite their theoretical presence?

Key findings

• At tanβ = 3, the resonance-enhanced cross section for hhh production reaches up to 300 fb, primarily driven by trilinear couplings.
• The cross section decreases to about 150 fb at higher MA, with the main contribution arising from the box diagram where H → hh decay proceeds via λHhhh.
• Quartic coupling contributions are suppressed by two orders of magnitude compared to trilinear diagrams, rendering λhhhh unmeasurable at the LHC.
• For tanβ = 30, the cross section remains nearly constant at ~6 fb due to large hhh coupling and no resonance, with no observable enhancement.
• The ratio of 2h to 3h production cross sections is approximately 10 at small tanβ, indicating that 3h production is significant but subdominant to 2h processes.
• The suppression of quartic coupling contributions is due to both small coupling strength and interference effects, not just phase space.