Effect of CP violation in the singlet-doublet dark matter model

Understand

We revisit the singlet-doublet dark matter model with a special emphasis on the effect of CP violation on the dark matter phenomenology.

• The CP violation in the dark sector induces a pseudoscalar interaction of a fermionic dark matter candidate with the SM Higgs boson.
• The pseudoscalar interaction helps the dark matter candidate evade the strong constraints from the dark matter direct detection experiments.
• We show that the model can explain the measured value of the dark matter density even if dark matter direct detection experiments do not observe any signal.