Data release: Atmospheric neutrino oscillation analysis with neutron tagging and an expanded fiducial volume in Super-Kamiokande I-V

Super-Kamiokande Atmospheric Neutrino Oscillation Analysis Data Release 2023

This data release accompanies the publication "Atmospheric neutrino oscillation analysis with neutron tagging and an expanded fiducial volume in Super-Kamiokande I-V." The information provided is divided into two sub-directories:

• bins: Contains data & MC counts in each analysis bin for different oscillation configurations
• chi2: Contains listings of chisquare values at each point in the oscillation parameter space scanned for the analyses described in the accompanying publication

Bin Information

This section describes the provided bin information. The `bin` subdirectory includes a ROOT file which contains binning information, data, and MC counts and MC summary statistics in each bin in the form of several ROOT trees. The contents of the ROOT file are also provided as text files within the same subdirectory.

There are 930 bins used for atmospheric neutrino data in the analysis. Each ROOT tree and text file contains sequential listing of information for each of the 930 bins, i.e. the first entry or line of each tree and text file corresponds to the first bin, and so on.

DISCLAIMER: The data and MC counts and summary statistics provided are not expected to be sufficient to identically reproduce the publication fit results. The publication fit results rely on response functions of the bins to variations in the systematic uncertainty parameters which are not included in this release. Additionally, the MC oscillation probabilities used in the publication were computed individually for each MC event and are not possible to reproduce exactly using the binned event information provided with this release.

Bin Definitions

The ROOT file contains a `BinInfoTree` which lists the sample name associated with each bin, and the upper and lower bin edges of the 2D binning scheme used to bin atmospheric neutrino events. The sample names describe the selections used to place events in each bin, e.g. "subgev" and "multigev" for sub-GeV and multi-GeV events, respectively. Since data from the different SK phases are divided into different analysis samples, each sample name also lists the range of SK phases included in the same, e.g. sk1-5 for SK I, SK II, SK III, SK IV, and SK V, or sk4-5 for SK IV and SK V only. The contents of this tree are also listed in the `bin/sk_2023_BinInfo.txt` file.

Data Counts

Observed atmospheric neutrino data counts in each bin are listed in the `DataTree` within the ROOT file. The contents of this tree are also listed in the `bin/sk_2023_Data.txt` file.

MC Counts and Summary Statistics

MC counts and summary statistics of the true MC energies and directions are provided for each true neutrino type in the ROOT trees named `MC*Tree`. The information is provided for three oscillation configurations: The best-fit oscillation parameters in the normal ordering (NO), the best-fit oscillation parameters in the inverted ordering (IO), and without oscillations (NoOsc).

The following summary statistics are provided for both the true neutrino energies and directions (cosine zenith angle) of MC events in each bin: Average, RMS, 2.3%, 15.9%, 50%, 84.1%, and 97.7% quantiles. The quantiles approximately correspond to -2, -1, 0, +1, and +2 sigma deviations from the median.

The ROOT tree MC information is duplicated in the text files found under the `bin/[normal,inverted,unoscillated]` subdirectories, corresponding to the three oscillation scenarios.

Chisquare Information

This section describes the provided chisquare information. We provide listings of the relative chisquare values with respect to the global best-fit point in the normal ordering. The listings are provided as text files: The first columns correspond to the oscillation parameters at each grid point, while the final column lists the chisquare value. Chisquare values are provided for both the theta13-free and theta13-constrained analyses.

ROOT files containing the 1D delta chisquare profiles for delta CP, and 2D delta chisquare profiles for allowed values of delta m^2 versus sin2 theta23 at 68% and 90% are also provided. There are two ROOT files corresponding to the contours from the theta13-free and theta13-constrained fits.

A ROOT macro which draws the contours is also provided. It can be run using the following command from the chi2 directory:

> root draw_sk_contours.cc