Measurement of neutron production in atmospheric neutrino interactions at the Sudbury Neutrino Observatory

• Published in: Physical review. D 2019-06, Vol.99 (11), p.1, Article 112007
• Main Authors: Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P.-L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM, Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Krüger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O’Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Orebi Gann, G. D., Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K.
• Format: Article
• Language: English
• Subjects: ATOMIC AND MOLECULAR PHYSICS; Computer simulation; Heavy water; Monte Carlo simulation; neutrino; Neutrinos; NUCLEAR PHYSICS AND RADIATION PHYSICS; Observatories; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 2470-0010; 2470-0029
• DOI: 10.1103/PhysRevD.99.112007

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.