A cancellation mechanism for dark matter-nucleon interaction

Understand

We consider a simple Higgs portal dark matter model, where the Standard Model is supplemented with a complex scalar whose imaginary part plays the role of WIMP dark matter (DM).

• We show that the direct DM detection cross section vanishes at tree level and zero momentum transfer due to a cancellation by virtue of a softly broken symmetry.
• This cancellation is operative for any mediator masses.
• As a result, our electroweak scale dark matter satisfies all of the phenomenological constraints quite naturally.