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Neutron Electric Dipole Moment in the Minimal Supersymmetric Standard Model

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 نشر من قبل Tomoyuki Inui
 تاريخ النشر 1995
  مجال البحث
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Neutron electric dipole moment (EDM) due to single quark EDM and to the transition EDM is calculated in the minimal supersymmetric standard model. Assuming that the Cabibbo-Kobayashi-Maskawa matrix at the grand unification scale is the only source of CP violation, complex phases are induced in parameters of soft supersymmetry breaking at low energies. Chargino one-loop diagram is found to give the dominant contribution of the order of $10^{-27}sim 10^{-29}:ecdot$cm for quark EDM, assuming the light chargino mass and the universal scalar mass to be $50$ GeV and $100$ GeV, respectively. Therefore the neutron EDM in this class of model is difficult to measure experimentally. Gluino one-loop diagram also contributes due to the flavor changing gluino coupling. The transition EDM is found to give dominant contributions for certain parameter regions.



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