科研之友
微信
新浪微博
Facebook
分享链接
摘要
There is evidence for a spectral line at E-gamma approximate to 130 GeV in the Fermi-LAT data that can be explained as dark mater particles annihilating into photons. We review a well known dark matter model that consists in a singlet Dirac fermion and a singlet scalar. The scalar implements spontaneous symmetry breaking in the dark sector, and is responsible for the communication between dark matter and standard model particles through a coupling to the Higgs. These interactions are suppressed by the mixing between the scalar and the Higgs. Therefore, the singlet fermionic dark matter is naturally a weakly interacting massive particle (WIMP) and can explain the observed relic density. We show that this model cannot produce the signal identified in the Fermi-LAT data. Thus, we propose a modification in the model by introducing a new scalar multiplet that carries electric charge and couples to the singlet scalar. It enhances the annihilation into two photons and succeeds in producing the observed signal. We also discuss the resulting increase of the branching ratio of the h -> gamma gamma process, which is consistent with measurements from the CMS experiments.
- 出版日期2014-8
