The Flavour Composition of the high-energy IceCube neutrinos

The recent detection of 37 high-energy neutrinos of astrophysical origin by the IceCube experiment at the South Pole 
has signalled the beginning of high-energy neutrino astronomy. At these energies, neutrinos are expected to be produced 
by pion disintegration after production in high-energy sources. This should lead to a democratic flavour composition at Earth  
of (1:1:1) electron : muon : tau neutrinos. I will present our analysis of the observed flavour composition of the IceCube 
events, based on the event topology and energy spectra, and show that the canonical (1:1:1) is not necessarily favoured 
by the data. I will demonstrate that current observations hint at some compelling puzzles, notably the lack of lower-energy 
muon neutrinos, as well as an absence of observed events in the expected Glashow resonance peak above 3 PeV.