Liberating Higgs couplings in supersymmetry

TL;DR

This paper investigates how low-scale spontaneous supersymmetry breaking can modify Higgs couplings in the MSSM, allowing for deviations from Standard Model predictions and providing new avenues for experimental tests at the LHC.

Contribution

It introduces a scenario where Higgs couplings are independently adjustable via soft parameters, breaking the usual MSSM degeneracy and offering distinctive phenomenological signatures.

Findings

Normalized Higgs coupling to tau leptons can be depleted.

Higgs coupling to photons can be enhanced.

Other Higgs couplings remain close to SM values.

Abstract

In the MSSM, the Higgs couplings to down-type quarks and leptons, normalized with respect to their corresponding Standard Model values, coincide at tree-level and this degeneracy is only slightly broken at the quantum level. Motivated by the latest results of the Higgs searches at the LHC and Tevatron, we explore the possibility of disentangling these couplings from each other by considering a scenario in which supersymmetry is broken spontaneously at a low scale. In such a scenario, all the Higgs couplings, except the ones to the Z and W bosons, receive tree level corrections that depend on the MSSM soft parameters. In particular, the corrections to the Yukawa couplings depend on the A-term soft parameter for the corresponding fermion, allowing for the freedom to break their usual relations, even in the MSSM decoupling limit. We highlight the main features of this scenario in terms of a benchmark point for which the normalized Higgs coupling to the tau leptons is depleted, the coupling to photons is enhanced, while all the other Higgs couplings, including the one to the bottom quarks, are close to their corresponding SM values. We also discuss the experimental bounds arising mainly from di-tau searches and comment on the discovery/exclusion prospects at the LHC.