Supersymmetric naturalness beyond MSSM

Naturalness of supersymmetric models

After presenting a simple procedure for testing naturalness (similar to Bayesian inference and not more subjective than it) we show that LEP2 experiments pose a naturalness problem for ‘conventional’ supersymmetric models. About 95% of the parameter space of minimal supergravity MSSM is excluded by LEP2 experiments. Moreover in this model electroweak baryogenesis, or detectable supersymmetric c...

Minimal Supersymmetric Standard Model (MSSM)

Beyond the Mssm *

Specific quasi-realistic superstring constructions often predict the existence of new TeV-scale physics which may be different in character from bottom-up motivated constructions. I describe examples of such beyond the MSSM physics, with special emphasis on heavy Z ′ gauge bosons and associated exotic particles. Implications of an extra U (1) ′ include a viable scienario for electroweak baryoge...

Beyond the MSSM

To increase the predictivity of the Minimal Supersymmetric Standard Model (MSSM), one needs to go to an underlying, more fundamental theory, where at least some of the many MSSM parameters can be determined by symmetries or by dynamics. Progress may come from four-dimensional superstring solutions and their effective supergravities. Summarizing some recent work [1–3], we introduce a class of ‘l...

Naturalness in low-scale SUSY models and “non-linear” MSSM

In MSSM models with various boundary conditions for the soft breaking terms ([Formula: see text]) and for a Higgs mass of 126 GeV, there is a (minimal) electroweak fine-tuning [Formula: see text] to [Formula: see text] for the constrained MSSM and [Formula: see text] for non-universal gaugino masses. These values, often regarded as unacceptably large, may indicate a problem of supersymmetry (SU...