Higgs-mediated FCNCs in the MSSM simplified
Prof. Dr. Sebastian Jäger (TU München)

I present a systematic study of the higgs sector of the MSSM with minimal flavour violation at large tan(beta) and tan(beta)-enhanced higher-order contributions to B-Bbar mixing. To this end I discuss the one-loop structure of the Higgs sector in the limit v << M_SUSY in full generality and identify an approximate U(1) symmetry in the low-energy effective two-higgs-doublet model in the phase of broken electroweak symmetry. By judiciously choosing the U(1) charges, one can identify four independent small parameters and show that any contribution to B-Bbar mixing that does not enter through the SM operator must be proportional to one of them. This allows for an exhaustive discussion of possible large corrections to the commonly used results in the literature. I discuss the phenomenological impact, the renormalization condition for tan(beta), and compare to earlier studies in the literature.