Related Experiment Video
Updated: Apr 12, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube
M G Aartsen1, M Ackermann2, J Adams3
1School of Chemistry and Physics, University of Adelaide, Adelaide, South Australia 5005, Australia.
Abstract:
A diffuse flux of astrophysical neutrinos above 100 TeV has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to 35 TeV and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for showerlike events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the (fe:fμ:fτ)⊕≈(1:1:1)⊕ flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on nonstandard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally tracklike composition of (0:1:0)⊕ is excluded at 3.3σ, and a purely showerlike composition of (1:0:0)⊕ is excluded at 2.3σ.
Related Concept Videos
Atomic Nuclei: Nuclear Spin State Population Distribution
Atomic Radii and Effective Nuclear Charge
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
Fermi Level Dynamics
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Atomic Spectroscopy: Effects of Temperature
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature...
Phase Transitions: Melting and Freezing

