High energy tau neutrinos

The intrinsic tau neutrino flux from cosmological and astrophysical sources has usually been considered negligible in comparison to the electron and muon neutrino fluxes. However, the inclusion of the tau neutrino component coming from hadronic decay at the source can significantly modify the tau neutrino spectrum expected at Earth. We report our results on the high energy tau neutrino production and its implications for the observation of high energy neutrino events.