|DATE||June 25 (Tue), 2019|
|TITLE||Dark matter in the conformally invariant extensions of the standard model|
We discuss two classically scale-invariant models with an anomaly-free set of two fermionic dark matters or with a scalar dark matter multiplet of global O(N) symmetry. In the fermionic dark matter model, we introduce U(1)_X gauge symmetry with new charge X in the dark sector in order to stabilize the mass of the scalar singlet with a new gauge boson. Our conformally invariant scalar potential generates the electroweak symmetry breaking via the Coleman-Weinberg mechanism, and a new scalar singlet mediator acquires its mass through radiative corrections of the fermionic dark matters and the new gauge boson or of the scalar dark matter as well as of the SM particles. Taking into account the collider bounds, we present the allowed region of new physics parameters satisfying the recent measurement of relic abundance. With the obtained parameter sets, we predict the elastic scattering cross section of the dark matter candidates into target nuclei for a direct detection of the dark matter. We also discuss the collider signatures and future discovery potentials of the new scalar singlet and gauge boson.