Measuring flavor ratios of high-energy astrophysical neutrinos

Abstract

We discuss the prospects for next generation neutrino telescopes, such as IceCube, to measure the flavor ratios of high-energy astrophysical neutrinos. The expected flavor ratios at the sources are φν e:φνμ:φν τ=1:2:0, and neutrino oscillations quickly transform these to 1:1:1. The flavor ratios can be deduced from the relative rates of showers (νe charged current, most ντ charged current, and all flavors neutral current), muon tracks (νμ charged current only), and tau lepton lollipops and double bangs (ντ charged current only). The peak sensitivities for these interactions are at different neutrino energies, but the flavor ratios can be reliably connected by a reasonable measurement of the ..