Neutron production in giga electron volt-scale neutrino interactions is a poorly studied process. We have measured the neutron multiplicities in atmospheric neutrino interactions in the Sudbury Neutrino Observatory experiment and compared them to the prediction of a Monte Carlo simulation using genie and a minimally modified version of geant4. We analyzed 837 days of exposure corresponding to Phase I, using pure heavy water, and Phase II, using a mixture of Cl in heavy water. Neutrons produced in atmospheric neutrino interactions were identified with an efficiency of 15.3% and 44.3%, for Phases I and II respectively. The neutron production is measured as a function of the visible energy of the neutrino interaction and, for charged current quasielastic interaction candidates, also as a function of the neutrino energy. This study is also performed by classifying the complete sample into two pairs of event categories: charged current quasielastic and non charged current quasielastic, and νμ and νe. Results show good overall agreement between data and Monte Carlo for both phases, with some small tension with a statistical significance below 2σ for some intermediate energies.
|Journal||Physical Review D|
|State||Published - Jun 18 2019|
Bibliographical noteFunding Information:
This research was supported by Natural Sciences and Engineering Research Council; Industry Canada; National Research Council; Northern Ontario Heritage Fund; Atomic Energy of Canada, Ltd.; Ontario Power Generation; High Performance Computing Virtual Laboratory; Canada Foundation for Innovation; Canada Research Chairs program (Canada); Department of Energy Office of Nuclear Physics; National Energy Research Scientific Computing Center; Alfred P. Sloan Foundation; National Science Foundation; the Queens Breakthrough Fund; Department of Energy National Nuclear Security Administration through the Nuclear Science and Security Consortium (United States); Science and Technology Facilities Council (formerly Particle Physics and Astronomy Research Council) (United Kingdom); and Fundação para a Ciência e a Tecnologia (Portugal). We thank the SNO technical staff for their strong contributions. We thank INCO (now Vale, Ltd.) for hosting this project in their Creighton mine. We also thank the Super-Kamiokande Collaboration for allowing us to use their data in our comparison.
© 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the »https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
ASJC Scopus subject areas
- Nuclear and High Energy Physics