Scalar dark matter and muon g-2 in a model * *Supported by the National Natural Science Foundation of China (12075043, 12147205)

Abstract

We consider a simple scalar dark matter model within the frame of gauged symmetry. A new gauge boson , as well as two scalar fields S and Φ, are introduced to the Standard Model (SM), where S and Φ are SM singlets but both carry charge. The real component and imaginary component of S can acquire different masses after spontaneously breaking symmetry, and the lighter one can play the role of dark matter, which is stabilized by an extra symmetry. We consider the possibility of light dark matter as well as the co-annihilation case in our model and present the current anomaly, Higgs invisible decay, dark matter relic density, and direct detection constraints on the parameter space. Direct detection gives the most stringent restriction on the model, and we found that although most of the parameter space is excluded, a mass region of a few GeV is still allowed where the co-annihilation process is also permitted in the model.