Measurement of atmospheric neutrino oscillations with three years of data from the full sky

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Introduction

In 2013, IceCube reported its first measurement of the neutrino oscillation parameters. This was the first time that neutrino oscillations were measured with precision at energies above 10 GeV. A year later, the collaboration presented a second analysis with three years of data that improved the precision by a factor of ten. The IceCube Collaboration has now published in Physical Review Letters a new measurement of the oscillation parameters that for the first time uses neutrinos from the full sky. These results are competitive with the best measurements to date.

+ Info: “Measurement of Atmospheric Neutrino Oscillations at 6-56 GeV with IceCube DeepCore,” IceCube Collaboration: M. G. Aartsen et al., Physical Review Letters 120, 071801 (2018). DOI: 10.1103/PhysRevLett.120.071801

See also the paper on arXiv.

Data release

Suggested citation for this dataset:

IceCube Collaboration (2018): Measurement of atmospheric neutrino oscillations with three years of data from the full sky. IceCube Neutrino Observatory. Dataset.
DOI: 10.21234/B4105H.

Click here to download (.zip, 140KB).

Included in the download are the following files:

  • chi2_map_NH – Δχ2 maps in 2D (Δm232, sin2(θ23)) for normal mass ordering, provided in 3 different formats (.dat, .pckl, and .root)
  • chi2_map_IH – Δχ2 maps in 2D (Δm232, sin2(θ23)) for inverted mass ordering, provided in 3 different formats (.dat, .pckl, and .root)
    The .dat files contain the value of Δm232 in eV2 (labeled “dm32”), the value of sin2(θ23) (labeled “sin^2(theta23)”), and the corresponding Δχ2 (labeled “DeltaChi2”). Δχ2 maps are defined relative to the best fit of each hierarchy in isolation.
    The .pckl files contain a dictionary with keys “dm32”, “sin2_theta23”, and “delta_chi2”.
    The .root files contain a tree named chi2_map with branches that have the same names as in the .pckl files.
  • contours.png – Example of the 90% CL contour from this data release (dark green and labeled “IC2017 without FC [NH]”) compared to that published in PRL (burnt orange and labeled “IC2017 FC [NH]”). The first is drawn using a constant Δχ2 value of 4.6 while the second was derived using the Feldman-Cousins approach.
  • IC2017_90CL_FC.dat – 90% CL contours obtained using the Feldman-Cousins approach. The first column has the values of sin2(θ23) while the second column contain the values of Δm232 in units of 10-3 eV2.
  • README – provides information about this release.

Additional information will be provided as follow-up data analyses are completed by the IceCube Collaboration.

For any questions about this data release, please write to data@icecube.wisc.edu.