The flavor-locked flavorful two Higgs doublet model

  • Wolfgang Altmannshofer
  • Stefania Gori
  • Dean J. Robinson
  • Douglas Tuckler
Open Access
Regular Article - Theoretical Physics


We propose a new framework to generate the Standard Model (SM) quark flavor hierarchies in the context of two Higgs doublet models (2HDM). The ‘flavorful’ 2HDM couples the SM-like Higgs doublet exclusively to the third quark generation, while the first two generations couple exclusively to an additional source of electroweak symmetry breaking, potentially generating striking collider signatures. We synthesize the flavorful 2HDM with the ‘flavor-locking’ mechanism, that dynamically generates large quark mass hierarchies through a flavor-blind portal to distinct flavon and hierarchon sectors: dynamical alignment of the flavons allows a unique hierarchon to control the respective quark masses. We further develop the theoretical construction of this mechanism, and show that in the context of a flavorful 2HDM-type setup, it can automatically achieve realistic flavor structures: the CKM matrix is automatically hierarchical with |V cb | and |V ub | generically of the observed size. Exotic contributions to meson oscillation observables may also be generated, that may accommodate current data mildly better than the SM itself.


Beyond Standard Model Higgs Physics Quark Masses and SM Parameters 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • Wolfgang Altmannshofer
    • 1
  • Stefania Gori
    • 1
  • Dean J. Robinson
    • 1
  • Douglas Tuckler
    • 1
  1. 1.Department of PhysicsUniversity of CincinnatiCincinnatiU.S.A.

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