LUX constraints on magnetic dark matter in a perturbative extension of the standard model with(out) naturality

We study phenomenological constraints in a simple SĒχy extension of the Standard Model with a 125-GeV Higgs, a vectorlike heavy electron (E), a complex scalar electron (S) and a Standard Model singlet Dirac fermion (χ). The interactions among the dark matter candidate χ and the Standard Model particles occur via loop-induced processes involving the Yukawa interaction SĒχy. The model is an explicit perturbative realization of so-called magnetic dark matter. The field content allows for a cancellation of quadratic divergences in the scalar masses at one loop, a phenomenon which we refer to as perturbative naturality. The basic model is constrained dominantly by direct detection experiments and its parameter space can be nearly entirely covered by upcoming ton-scale direct detection experiments. We conclude this work by discussing different variations of the model. © 2014 American Physical Society