Mass and life time of heavy dark matter decaying into IceCube PeV neutrinos

Abstract

Considering that the ultrahigh energy (UHE) upgoing muon neutrino events around the PeV energy region observed by the IceCube are due to the decay of superheavy dark matter to neutrinos, we constrain the mass of the decaying dark matter and its decay lifetime using the IceCube analysis of these neutrinos in the PeV region. The theoretical fluxes are computed by adopting the procedure given in the reference [1,2], where the DGLAP numerical evolutions of QCD cascades as well as electroweak corrections are included for evolving the decay process of the superheavy dark matter. Our results indicate that to explain the IceCube events around PeV region the decaying dark matter mass mχ would be ∼5×107 GeV with the decay lifetime τ∼7×1028 sec.