Comparison of high-energy galactic and atmospheric tau neutrino flux

We compare the tau neutrino flux arising from the galaxy and the earth atmosphere for 103⩽E/GeV⩽1011. The intrinsic and oscillated tau neutrino fluxes from both sources are calculated. The intrinsic galactic ντ flux (E⩾103 GeV) is calculated by considering the interactions of high-energy cosmic-rays with the matter present in our galaxy, whereas the oscillated galactic ντ flux is coming from the oscillation of the galactic νμ flux. For the intrinsic atmospheric ντ flux, we extend the validity of a previous calculation from E⩽106 GeV up to E⩽1011 GeV. The oscillated atmospheric ντ flux is, on the other hand, rather suppressed. We find that, for 103⩽E/GeV⩽5×107, the oscillated ντ flux along the galactic plane dominates over the maximal intrinsic atmospheric ντ flux, i.e., the flux along the horizontal direction. We also briefly mention the presently envisaged prospects for observing these high-energy tau neutrinos.