Natural ranges of supersymmetric signals Original Research Article

The LEP2 experiments pose a serious naturalness problem for supersymmetric models. The problem is stronger in gauge mediation than in supergravity models. Particular scenarios, like electroweak baryogenesis or gauge mediation with light messengers, are strongly disfavoured. Searching a theoretical reason that naturally explains why supersymmetry has not been found poses strong requests on model building. If instead an unlikely (p ∼ 5%) numerical accident has hidden supersymmetry to LEP2, we compute the naturalness distribution of values of allowed sparticle masses and supersymmetric loop effects. We find that b → sy remains a very promising signal of minimal supersymmetry even if there is now a 20% (4%) probability that colored particles are heavier than 1 TeV (3 TeV). We study how much other effects are expected to be detectable.