Unification and low-energy supersymmetry at one and two-loop orders

Nir Polonsky

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arXiv · hep-ph/9411378

Unification and low-energy supersymmetry at one and two-loop orders

Nir Polonsky

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Abstract

The status of coupling constant unification -- assuming the validity of the standard model or of its minimal supersymmetric extension at high energies -- and of relations between various Yukawa couplings (assuming the supersymmetri extension) which are implied in certain grand-unified theories, are studied in detail. Theoretical uncertainties in the calculations are emphasized, and low-energy constraints and predictions are derived. In particular, we find that bottom-tau unification favors a Higgs boson lighter than 110 GeV. The structure of the vacuum in the model studied is also discussed. Implications of embedding supersymmetric models in grand-unified theories are further explored and are shown to affect the soft supersymmetry breaking mass parameters of the models, and thus the spectrum at low-energy.

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Nir Polonsky. 1994-11-23. Unification and low-energy supersymmetry at one and two-loop orders. https://arxiv.org/abs/hep-ph/9411378

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