Research Highlights: Neutrino Physics
The DeepCore subdetector allows IceCube to extend the measurement of the neutrino flux from 100 TeV down to below 10 GeV. At these energies, we observe atmospheric neutrino oscillations and perform searches for sterile neutrinos. We have measured the atmospheric oscillation parameters with a precision compatible with and comparable to those of the dedicated oscillation experiments, such as MINOS, T2K, or Super-Kamiokande.
IceCube has also conducted two searches for light sterile neutrinos, one using high-energy atmospheric neutrinos detected in IceCube and another using low-energy neutrinos detected in DeepCore. None of the searches found evidence for anomalous muon neutrino disappearance and the limits exclude at 99% confidence level the allowed region from appearance experiments such as LSND and MiniBooNE. The search with low-energy neutrinos provided exclusion limits for the sterile neutrino oscillation parameters, with a new world-best limit on the |Uτ4|2 mixing matrix element.