hierarchy between S$_{D}$ and δ$_{L}$ . In Fig. 10, we give the FSR and VIB contributions to the gamma-ray spectrum for three different DM mass cases ( m$_{D}$ = 2 . 5 , 4 and 6 TeV). Here we have fixed the triplet mass m$_{δ}$$_{L}$ = 1 TeV and the DM lifetime τ$_{D}$ = 0 . 9 × 10 26 s. We can see that with m$_{D}$ increasing, the VIB contribution becomes more significant relative to FSR. For a low m$_{D}$ = 2 . 5 TeV, the contribution from VIB relative to that of FSR is only ∼ 7%. But for a larger m$_{D}$ = 6 TeV, the contribution can reach ∼ 20% which is non-negligible. 

## IV. CONCLUSIONS 

We have discussed the DM cascade decay induced by tiny soft C -violating interactions in an extension of a left-right symmetric model in which the DM particle is identified as a gauge singlet scalar. In this scenario, the DM particle may decay favorably into leptonic final states through the intermediate SU (2)$_{L}$ triplets. We have explored the parameter space which can well explain the current PAMELA and Fermi-LAT or ATIC experimental data. It is shown that this scenario predicts significant associating signals in the flux of high energy neutrinos and gamma-rays, which is due to the correlated couplings to neutrinos and the extra contributions from the charged components of the triplet. We have found that the predicted neutrino-induced muon flux is dominated by the contribution from the neutrinos directly from the triplet decay. The gamma-ray radiation from the charged triplet scalars through VIB process can be significant in the case that the triplets are much lighter that the DM particle. 

## Acknowledgments 

This work is supported in part by the National Basic Research Program of China (973 Program) under Grants No. 2010CB833000; the National Nature Science Foundation of China (NSFC) under Grants No. 10975170, No. 10821504 and No. 10905084; and the Project of Knowledge Innovation Program (PKIP) of the Chinese Academy of Science. 

