Cosmic Ray Positron and Electron Excess from Hidden-Fermion Dark Matter   Decays
  The anomalies observed in recent cosmic ray experiments seem to strongly constrain the nature of the dark matter. In this letter, we investigate a possibility of the fermionic dark matter with a minimal extension of the standard model. We found that the dark matter decays caused by the dimension six operators can naturally explain the anomalies. 
Koichi Hamaguchi, Satoshi Shirai and T. T. Yanagida