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Bounds on flavour violating parameters in supersymmetry

Thomas Besmer·Christoph Greub·Tobias Hurth
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Abstract

We investigate the constraints on the flavour violating parameters from the decay B --> X_s gamma, taking into account the interplay of the various sources of flavour violation in the unconstrained MSSM. We present a systematic leading logarithmic QCD analysis of these model-independent constraints, including contributions from gluinos, neutralinos, charginos, charged Higgs bosons and interferences between them. We show that two simple combinations of elements of the down squark mass matrix are stringently bounded over large parts of the parameter space where only weak assumptions on the hierarchical structure of the squark mass matrices are made. We also briefly analyse up to which values SUSY contributions, compatible with B --> X_s gamma, can enhance the Wilson coefficient C_8(m_W), which plays an important role in the phenomenology of charmless hadronic B decays.

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Thomas Besmer, Christoph Greub, Tobias Hurth. 2001-05-28. Bounds on flavour violating parameters in supersymmetry. https://doi.org/10.1016/s0550-3213(01)00306-6

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