The high-energy galactic tau neutrino flux and its atmospheric background

Abstract

We compare the tau neutrino flux arising from the galaxy and the earth atmosphere for $10^{3} \leq E/{GeV} \leq 10^{11}$. The intrinsic and oscillated tau neutrino fluxes from both sources are considered. We find that, for $E\geq 10^3$ GeV, the oscillated $\nu_{\tau}$ flux along the galactic plane dominates over the maximal intrinsic atmospheric $\nu_{\tau}$ flux, i.e., the flux along the horizontal direction. We also briefly comment on the prospects for observing these high-energy tau neutrinos.