Decoupling and the Radiatively-Corrected MSSM Higgs Sector

In the decoupling limit of a non-minimal Higgs sector, the lightest CP-even Higgs boson (h) is indistinguishable from the Standard Model (SM) Higgs boson. In the two-Higgs-doublet sector of the MSSM, the approach to the decoupling limit (for mA ≫ mZ) persists, even in the presence of potentially large (tanβ-enhanced) radiative corrections to the hbb̄ coupling. Radiative corrections can also generate an accidental cancellation between tree-level and one-loop terms, resulting in a SM-like Higgs boson for moderate mA outside the decoupling regime. Invited talk at the 6th International Symposium on Radiative Corrections: Application of Quantum Field Theory to Phenomenology—RADCOR 2002 and 6th Zeuthen Workshop on Elementary Particle Theory: Loops and Legs in Quantum Field Theory September 8–13, 2002, Kloster Banz, Germany