Constraints on Natural Supersymmetry from Electroweak Precision Tests

Abstract

The observed Higgs boson mass and the naturalness argument leave us a narrow window for the soft mass spectrum in natural supersymmetry that can be studied through the electroweak precision tests (EWPTs). We divide the analysis into the Higgs sector constrained by the charged Higgs mass bound, the neutralino-chargino sector constrained by the chargino mass bound, and the third-generation squark sector tightly constrained by the observed Higgs mass. Total contributions to EWPTs in the MSSM and NMSSM are both presented. It turns out that natural MSSM is excluded at 68\% CL but consistent at 95\% CL, whereas natural NMSSM with nearly degenerate conditions is excluded at 68\% CL but consistent at 99\% CL for $\lambda\leq 0.6$.