Measurement of atmospheric anti-neutrino/neutrino-ratio with Icecube

Models on atmospheric neutrino flux suffer from a uncertainty of about 20% from modeling hadronic interactions. It is therefore interesting to measure parameters that may constrain this. Cherenkov detectors like IceCube in general can not differentiate between particles and antiparticles. However for charged current interactions where hadronic cascade and a sufficient fraction of the created leptons energy is contained, it is possible to measure the inelasticity from the energy deposition along the track. Particles and antiparticles experience different quark density functions in the nucleus, the cross section as a function of inelasticity differs. Selecting a pure sample of sufficiently contained events and fitting the Monte-Carlo event rate as a function of inelasticity to the data allows measuring the neutrino-antineutrino ratio.