The Inert Doublet Model

Implementation authors

• Andreas Goudelis (andreas.goudelis@…)
  • Laboratoire d'Annecy-le-Vieux de Physique Theorique, Annecy, France
• Björn Herrmann (herrmann@…)
  • Laboratoire d'Annecy-le-Vieux de Physique Theorique, Annecy, France
• Oscar Stal (oscar.stal@…)
  • Oscar Klein Center, Stockholm, Sweden

(work done in part at the Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany)

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Model description

This is the FeynRules model file for the Inert Doublet Model, , i.e. the Standard Model augmented by an additional complex scalar SU(2) doublet and an unbroken Z₂ symmetry under which all SM particles are even while the extra doublet is odd.

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Files

• InertDoublet.tar.gz : the FeynRules model files and the output for CalcHEP, UFO and FeynArts.
• IDMload.nb : example mathematica notebook to load the file.

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Validation

• All sectors of the model have been cross-checked against an independent implementation of the IDM using the SARAH package. A very large number of processes involving all model particles and vertices were computed, and complete numerical agreement was found. Moreover, all beta functions have been calculated using both implementations and agree perfectly.

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References

If you use these model files, please cite

• A. Goudelis, B. Herrmann, O. Stal, Dark matter in the Inert Doublet Model after the discovery of a Higgs-like boson at the LHC, JHEP 1309 (2013) 106, ​arXiv:1303.3010 [hep-ph].
• G. Belanger, B. Dumont, A. Goudelis, B. Herrmann, S. Kraml, D. Sengupta, Dilepton constraints in the Inert Doublet Model from Run 1 of the LHC, Phys.Rev. D91 (2015) 11, 115011, ​arXiv:1503.07367 [hep-ph].

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Notes

• The implementation comes in both Feynman and Unitary gauge, which can be chosen from within the InertDoublet.fr file.
• The model file follows the older (pre v1.8) FeynRules notations, but works perfectly with version 1.8.
• The inert doublet particles carry tildes (~) in their particle names. This is in compliance to the CalcHEP/MicrOMEGAs conventions, in which all Z₂-odd particles must be named with tildes. In other programs, the user might have to remove them.
• The model files include an effective vertex for the Higgs-glu-glu coupling
• Update 11/2024: The user can choose which form he/she wants for the CKM matrix. Three possibilities are included: i) Diagonal (no CKM mixing), ii) Absolute values of the CKM matrix elements iii) Wolfenstein parametrisation up to third order in lambda with lambda, A, rho and eta as external parameters. The default choice is ii) . It can be changed by commenting/uncommenting the relevant lines in the Parameters.fr file and re-running the IDMload.nb notebook.