Journal of High Energy Physics

, 2018:73 | Cite as

The C2HDM revisited

  • Duarte Fontes
  • Margarete Mühlleitner
  • Jorge C. Romão
  • Rui Santos
  • João P. Silva
  • Jonas Wittbrodt
Open Access
Regular Article - Theoretical Physics


The complex two-Higgs doublet model is one of the simplest ways to extend the scalar sector of the Standard Model to include a new source of CP-violation. The model has been used as a benchmark model to search for CP-violation at the LHC and as a possible explanation for the matter-antimatter asymmetry of the Universe. In this work, we re-analyse in full detail the softly broken 2 symmetric complex two-Higgs doublet model (C2HDM). We provide the code C2HDM_HDECAY implementing the C2HDM in the well-known HDECAY program which calculates the decay widths including the state-of-the-art higher order QCD corrections and the relevant off-shell decays. Using C2HDM_HDECAY together with the most relevant theoretical and experimental constraints, including electric dipole moments (EDMs), we review the parameter space of the model and discuss its phenomenology. In particular, we find cases where large CP-odd couplings to fermions are still allowed and provide benchmark points for these scenarios. We examine the prospects of discovering CP-violation at the LHC and show how theoretically motivated measures of CP-violation correlate with observables.


Beyond Standard Model CP violation Higgs Physics 


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

  1. 1.Departamento de Física and CFTP, Instituto Superior TécnicoUniversidade de LisboaLisboaPortugal
  2. 2.Institute for Theoretical Physics, Karlsruhe Institute of TechnologyKarlsruheGermany
  3. 3.ISEL — Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de LisboaLisboaPortugal
  4. 4.Centro de Física Teórica e Computacional, Faculdade de CiênciasUniversidade de LisboaLisboaPortugal
  5. 5.LIP, Departamento de FísicaUniversidade do MinhoBragaPortugal
  6. 6.Deutsches Elektronen-Synchrotron DESYHamburgGermany

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