Sensitivities of IceCube DeepCore Detector to Signatures of Low-Mass Dark Matter in the Galactic Halo

We discuss the event rate in DeepCore array due to neutrino flux produced by annihilations and decays of galactic dark matter. This event rate is calculated with a 10 GeV threshold energy, which is smaller than the threshold energy taken in previous works. Taking into account the background event rate due to the atmospheric neutrino flux, we evaluate the sensitivity of DeepCore array for probing dark matter annihilation cross section and decay time. The sensitivity studies include the annihilation modes $\chi\chi\to b\bar{b}, \ \tau^+ \tau^-$, \ $\mu^+\mu^-$, and $\nu\bar{\nu}$, and decay modes $\chi\to b\bar{b}, \ \tau^+ \tau^-$, \ $\mu^+\mu^-$, and $\nu\bar{\nu}$. We compare our results with corresponding constraints derived from observations of WMAP, ACT and Fermi-LAT.