IceCube bounds on sterile neutrinos above 10 eV

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We study the capabilities of IceCube to search for sterile neutrinos with masses above 10 eV by analyzing its $\nu_\mu$ disappearance atmospheric neutrino sample.

• We find that IceCube is not only sensitive to the mixing of sterile neutrinos to muon neutrinos, but also to the more elusive mixing with tau neutrinos through matter effects.
• The currently released 1-year data shows a mild (around 2$\sigma$) preference for non-zero sterile mixing, which overlaps with the favoured region for the sterile neutrino interpretation of the ANITA upward shower.
• Although the null results from CHORUS and NOMAD on $\nu_\mu$ to $\nu_\tau$ oscillations in vacuum disfavour the hint from the IceCube 1-year data, the relevant oscillation channel and underlying physics are different.