Results

Measurement of neutrino and antineutrino oscillations by the T2K experiment, including a new additional sample of electron neutrino interactions in the far detector

September 13, 2017

This data release pertains to this paper and includes results from both the frequentist and the Bayesian analyses presented there.

Both the tar files include a README document as well as several ROOT files with the results for different oscillation parameters.

For the frequentist analysis (T2K_VALOR_Data_release), each ROOT file contains the best fit point, the 68% and 90% CL contours, the χ2 = –2 Δln(ℒ) and Δχ2 map.

For the Bayesian analysis (jointfit2016_mach3.tar), each ROOT file contains the best fit point (in 2D and 4D modes), the 68% and 90% credible intervals, the 68% and 90% contours and the posterior probability density.

Search for Lorentz and CPT violation using sidereal time dependence of neutrino flavor transitions over a short baseline

June 28, 2017

This data release pertains to this paper.

The tar file for this release is here: LVOfficialData.

This includes a README document as well as a ROOT file.

The ROOT file contains several histograms providing the distribution of neutrino events per POT with respect to the local sidereal phase for all the T2K events from run 1 to 4, for the day-only and night-only events. An additional histogram provides the result from the null hypothesis test by showing the magnitude of each sidereal mode extracted from the data by a Fast Fourier transform method.  Finally, this file provide the best fit values as well as the 68% and 95% credible intervals for each SME parameter obtained by fitting the data with a binned likelihood function.  Note that in this fit, the correlation between the parameters are not negligible. The two-point correlations obtained by marginalization over other parameters are also provided.

Updated measurements of muon neutrino and antineutrino disappearance

April 20, 2017

This data release pertains to this paper.

The tar file for this data release includes a README document as well as a ROOT file.
The ROOT file contains the best fit point, the $\chi^{2}=-2 \Delta \ln \mathcal{L}$ distribution, and the contours that define the 68\% and 90\% confidence regions in the $\sin^2 \theta_{23}$ Vs $\Delta m^2_{32}$ plane. All those results correspond to the simultaneous fit of the 1 ring muon-like events recorded during neutrino and antineutrino running modes. The results are given separately for the parameters describing the disappearance of muon neutrinos and of muon antineutrinos, and are provided for the normal and inverted mass hierarchy cases.

t2kdata-numu-numubar-disap-2016

First combined analysis of neutrino and antineutrino oscillations at T2K

February 11, 2017

This data release pertains to this paper.

The tar file for this data release includes a README document
as well as a ROOT file with the $-2 \Delta \ln \mathcal{L}$ distributions of
$\sin^2 \theta_{23}$ Vs $\Delta m^2_{32}$ ($\theta_{13}$ constrained with the PDG2015 global fit result),
$\sin^2 \theta_{13}$ Vs $\delta_{CP}$ (T2K only data) and
$\delta_{CP}$ and mass ordering ($\theta_{13}$ constrained with the PDG2015 global fit result),
Also the contours that define the 68\% and 90\% confidence regions of
$\sin^2 \theta_{23}$ Vs $\Delta m^2_{32}$ and
$\sin^2 \theta_{13}$ Vs $\delta_{CP}$ are provided.

The data files are contained in this tarball: T2KJointNuNuBarOscillation_Run17c_2016 .

Neutrino beam flux prediction 2016

October 5, 2016

The files in the following archive file contain the neutrino and antineutrino beam flux predictions for the T2K ND280 (near) and Super-Kamiokande (far) detectors. It supersedes the previous flux release in 2013.
The original description of the flux predictions is published in this paper. Since the publication, the flux prediction has been updated with new thin target data from the NA61/SHINE experiment, and flux predictions for antineutrino enhanced beam operation have been produced. The NA61/SHINE thin target measurements of π±, K±, KS0, Λ and p production are published in Eur. Phys. J. C (2016) 76:84. The updated flux prediction is described in Phys. Rev. D 91, 072010 (2015).

The provided flux predictions include no neutrino oscillations.

This tar file contains the flux predictions as well as a README.pdf file with detailed information on the included files:
T2K flux prediction 2016

 

 

First Measurement of the Muon Neutrino Charged Current Single Pion Production Cross Section on Water with the T2K Near Detector

May 26, 2016

These data pertain to this paper.

The tar file for this data release includes a README document in PDF format and various csv files containing pion and muon kinematics as well as a ROOT file with the differential cross-section results and the muon neutrino flux histogram for T2K Run I-IV.
First Measurement of the Muon Neutrino Charged Current Single Pion Production Cross Section on Water with the T2K Near Detector

Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam

May 12, 2016

This data release pertains to this paper.

The tar file for this data release includes a README document in PDF format, and a ROOT file.
The ROOT file contains the best-fit points in the sin223)-Δm2 space, the 2D χ2 surface, 68% and 90% 2D confidence level contours, and 1D χ2 surfaces for both sin223) and Δm2.
All results are given for both normal and inverted hierarchy.
Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam

Measurement of double-differential muon neutrino charged-current interactions on C8H8 without pions in the final state using the T2K off-axis beam

February 17, 2016

These data pertain to this paper.

The tar file for this data release includes a README document in PDF format and various txt files containing the measured energy dependent CC0pi cross section and the covariance matrices for the two analyses presented in the paper. The results are presented in bins of muon momentum for separate muon angular ranges. The covariance matrices are provided separately for statistical uncertainties, systematic uncertainties and flux normalization uncertainty.
Measurement of double-differential muon neutrino charged-current interactions on C8H8 without pions in the final state using the T2K off-axis beam

Measurement of the νμ CCQE cross section on carbon with the ND280 detector at T2K

May 27, 2015

This data release pertains to the paper this paper.

The tar file for this data release includes a README document in PDF format and 2 csv files containing the measured energy dependent CCQE cross section and the covariance matrix describing the fractional uncertainty on these data. The README file gives information on how to interpret the numbers within the CSV file.
Measurement of the νμ CCQE cross section on carbon with the ND280 detector at T2K

Measurement of the νμ charged current quasi-elastic cross-section on carbon with the T2K on-axis neutrino beam

March 27, 2015

This data release pertains to this paper. The tar file for this data release includes a README document in PDF format and 3 ROOT files.

The ROOT files contain the neutrino flux information, the selection efficiency and nominal distribution information, and the systematic error covariance of the cross section results.
Measurement of the νμ charged current quasi-elastic cross-section on carbon with the T2K on-axis neutrino beam