1. Search for neutral-current induced single photon production at the ND280 near detector in T2K
- Author
-
Ministerio de Economía y Competitividad (España), T2K Collaboration, Abe, K., Akutsu, R., Ali, A., Andreopoulos, C., Anthony, L., Antonova, M., Aoki, Shohei, Ariga, A., Ashida, Y., Awataguchi, Y., Azuma, Y., Ban, S., Barbi, M., Barker, G.J., Barr, G., Barry, C., Batkiewicz-Kwasniak, M., Bench, F., Berardi, V., Berkman, S., Berner, R.M., Berns, L., Bhadra, S., Bienstock, S., Blondel, A., Bolognesi, S., Bourguille, B., Boyd, S.B., Brailsford, D., Bravar, A., Bronner, C., Avanzini, M.B., Calcutt, J., Campbell, T., Cao, S., Cartwright, S.L., Catanesi, M.G., Cervera Villanueva, Anselmo, Chappell, A., Checchia, C., Cherdack, D., Chikuma, N., Christodoulou, G., Coleman, J., Collazuol, G., Coplowe, D., Cudd, A., Dabrowska, A., Fernandez Menendez, Pablo, Izmaylov, A., Jesus, C., Labarga, L., Lux, T., Novella, Pau, Vargas, D., Ministerio de Economía y Competitividad (España), T2K Collaboration, Abe, K., Akutsu, R., Ali, A., Andreopoulos, C., Anthony, L., Antonova, M., Aoki, Shohei, Ariga, A., Ashida, Y., Awataguchi, Y., Azuma, Y., Ban, S., Barbi, M., Barker, G.J., Barr, G., Barry, C., Batkiewicz-Kwasniak, M., Bench, F., Berardi, V., Berkman, S., Berner, R.M., Berns, L., Bhadra, S., Bienstock, S., Blondel, A., Bolognesi, S., Bourguille, B., Boyd, S.B., Brailsford, D., Bravar, A., Bronner, C., Avanzini, M.B., Calcutt, J., Campbell, T., Cao, S., Cartwright, S.L., Catanesi, M.G., Cervera Villanueva, Anselmo, Chappell, A., Checchia, C., Cherdack, D., Chikuma, N., Christodoulou, G., Coleman, J., Collazuol, G., Coplowe, D., Cudd, A., Dabrowska, A., Fernandez Menendez, Pablo, Izmaylov, A., Jesus, C., Labarga, L., Lux, T., Novella, Pau, and Vargas, D.
- Abstract
Neutrino neutral-current (NC) induced single photon production is a subleading order process for accelerator-based neutrino beam experiments including T2K. It is, however, an important process to understand because it is a background for electron (anti)neutrino appearance oscillation experiments. Here, we performed the first search of this process below 1 GeV using the finegrained detector at the T2K ND280 off-axis near detector. By reconstructing single photon kinematics from electron positron pairs, we achieved 95% pure gamma ray sample from 5.738 1020 protons-on-targets neutrino mode data. We do not find positive evidence of NC induced single photon production in this sample. We set the model-dependent upper limit on the cross-section for this process, at 0.114 10-38 cm2 (90% C.L.) per nucleon, using the J-PARC off-axis neutrino beam with an average energy of .En. ~ 0.6 GeV. This is the first limit on this process below 1.GeV which is important for current and future oscillation experiments looking for electron neutrino appearance oscillation signals.
- Published
- 2019