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Simple model for large CP violation in charm decays, B-physics anomalies, muon g-2, and Dark Matter

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 نشر من قبل Lorenzo Calibbi
 تاريخ النشر 2019
  مجال البحث
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We present a minimal extension of the Standard Model that can simultaneously account for the anomalies in semi-leptonic B meson decays and the muon g-2, give large CP violation in charm decays (up to the value recently measured by LHCb), and provide thermal-relic dark matter, while evading all constraints set by other flavour observables, LHC searches, and dark matter experiments. This is achieved by introducing only four new fields: a vectorlike quark, a vectorlike lepton, and two scalar fields (a singlet and a doublet) that mix due to the electroweak symmetry breaking and provide the dark matter candidate. The singlet-doublet mixing induces chirally-enhanced dipole transitions, which are crucial for the explanation of the muon g-2 discrepancy and the large charm CP violation, and allows to achieve the observed dark matter density in wide regions of the parameter space.



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