Determination of the νe and total B8 solar neutrino fluxes using the Sudbury Neutrino Observatory Phase I data set

Authors

B. Aharmim, Laurentian University
Q. R. Ahmad, University of Washington
S. N. Ahmed, Queen’s University
R. C. Allen, University of California, Irvine
T. C. Andersen, University of Guelph
J. D. Anglin, National Research Council Canada
G. Bühler, University of California, Irvine
J. C. Barton, University of Oxford
E. W. Beier, University of Pennsylvania
M. Bercovitch, National Research Council Canada
M. Bergevin, University of Guelph
J. Bigu, Laurentian University
S. D. Biller, University of Oxford
R. A. Black, University of Oxford
I. Blevis, Carleton University
R. J. Boardman, University of Oxford
J. Boger, United States Department of Energy
E. Bonvin, Queen’s University
M. G. Boulay, Los Alamos National Laboratory
M. G. Bowler, University of Oxford
T. J. Bowles, Los Alamos National Laboratory
S. J. Brice, Fermi National Accelerator Laboratory
M. C. Browne, Los Alamos National Laboratory
T. V. Bullard, University of Washington
T. H. Burritt, University of Washington
J. Cameron, University of Oxford
Y. D. Chan, Lawrence Berkeley National Laboratory
H. H. Chen, University of California, Irvine

Document Type

Article

Publication Date

4-27-2007

Abstract

This article provides the complete description of results from the Phase I data set of the Sudbury Neutrino Observatory (SNO). The Phase I data set is based on a 0.65 kiloton-year exposure of 2H2O (in the following denoted as D2O) to the solar B8 neutrino flux. Included here are details of the SNO physics and detector model, evaluations of systematic uncertainties, and estimates of backgrounds. Also discussed are SNO's approach to statistical extraction of the signals from the three neutrino reactions (charged current, neutral current, and elastic scattering) and the results of a search for a day-night asymmetry in the νe flux. Under the assumption that the B8 spectrum is undistorted, the measurements from this phase yield a solar νe flux of (νe)=1.76-0.05+0. 05(stat.)-0.09+0.09(syst.)×106 cm-2 s-1 and a non-νe component of (νμτ)=3.41-0.45+0.45(stat.)-0.45+0.48(syst.)×106 cm-2 s-1. The sum of these components provides a total flux in excellent agreement with the predictions of standard solar models. The day-night asymmetry in the νe flux is found to be Ae=7.0±4.9(stat.)-1.2+1.3%(syst.), when the asymmetry in the total flux is constrained to be zero. © 2007 The American Physical Society.

Publication Source (Journal or Book title)

Physical Review C - Nuclear Physics

Recommended Citation

Aharmim, B., Ahmad, Q., Ahmed, S., Allen, R., Andersen, T., Anglin, J., Bühler, G., Barton, J., Beier, E., Bercovitch, M., Bergevin, M., Bigu, J., Biller, S., Black, R., Blevis, I., Boardman, R., Boger, J., Bonvin, E., Boulay, M., Bowler, M., Bowles, T., Brice, S., Browne, M., Bullard, T., Burritt, T., Cameron, J., Chan, Y., & Chen, H. (2007). Determination of the νe and total B8 solar neutrino fluxes using the Sudbury Neutrino Observatory Phase I data set. Physical Review C - Nuclear Physics, 75 (4) https://doi.org/10.1103/PhysRevC.75.045502