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Yukawa Deflected Gauge Mediation

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 نشر من قبل Eduardo Ponton
 تاريخ النشر 2001
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We consider models which are natural extensions of those where supersymmetry is broken at low energy scales and transmitted to visible matter by gauge interactions. We investigate the situation where the quark and lepton superfields of the MSSM are localized to a brane in a higher dimensional space while the messenger fields and the sector which breaks supersymmetry dynamically are localized to another brane in the same space. The MSSM gauge and Higgs fields are assumed to propagate in the bulk. If some of the messenger fields and the Higgs fields have the same quantum numbers, this allows the possibility of mixing between these fields so that the physical Higgs and messenger fields are admixtures of the brane and bulk fields. This manifests itself in direct couplings of the quark and lepton fields to the physical messengers that are proportional to the MSSM Yukawa couplings and hence preserve the flavor structure of the CKM matrix. The result is new contributions to the soft supersymmetry breaking parameters that are related to the Yukawa couplings and which therefore naturally satisfy the constraints from FCNCs. For messenger scales greater then 1000 TeV these new contributions are parametrically of the same order of magnitude as gauge mediation. This scenario naturally avoids the cosmological problems associated with stable messengers and admits a simple and natural solution to the $mu$ problem based on the NMSSM.

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