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arXiv · 0910.2732

Extra vector-like matter and the lightest Higgs scalar boson mass in low-energy supersymmetry

Stephen P. Martin
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Abstract

The lightest Higgs scalar boson mass in supersymmetry can be raised significantly by extra vector-like quark and lepton supermultiplets with large Yukawa couplings but dominantly electroweak-singlet masses. I consider models of this type that maintain perturbative gauge coupling unification. The impact of the new particles on precision electroweak observables is found to be moderate, with the fit to Z-pole data as good or better than that of the Standard Model even if the new Yukawa couplings are as large as their fixed-point values and the extra vector-like quark masses are as light as 400 GeV. I study the size of corrections to the lightest Higgs boson mass, taking into account the fixed-point behavior of the scalar trilinear couplings. I also discuss the decay branchings ratios of the lightest new quarks and leptons and general features of the resulting collider signatures.

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Stephen P. Martin. 2009-10-14. Extra vector-like matter and the lightest Higgs scalar boson mass in low-energy supersymmetry. https://doi.org/10.1103/physrevd.81.035004

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