The deployment of DeepCore array significantly lowers IceCube's energy threshold to about 10 GeV and enhances the sensitivity of detecting neutrinos from annihilations and decays of light dark matter. To match this experimental development, we calculate the track event rate in DeepCore array due to neutrino flux produced by annihilations and decays of galactic dark matter. We also calculate the background event rate due to the atmospheric neutrino flux for evaluating the sensitivity of DeepCore array to galactic dark matter signatures. Unlike previous approaches, which set the energy threshold for track events at around 50 GeV (this choice avoids the necessity of including the oscillation effect in the estimation of atmospheric background event rate), we have set the energy threshold at 10 GeV to take full advantage of DeepCore array. We compare our calculated sensitivity with those obtained by setting the threshold energy at 50 GeV. We conclude that our proposed threshold energy significantly improves the sensitivity of DeepCore array to the dark matter signature for m χ<100GeV in the annihilation scenario and m χ<300GeV in the decay scenario.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - 25 Jan 2012|