Search for neutral-current induced single photon production at the ND280 near detector in T2K

Journal article

All rights reserved. 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.

Authors: Abe, K; Akutsu, R; Ali, A; Andreopoulos, C; Anthony, L

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: Journal of Physics G: Nuclear and Particle Physics
• Volume: 46
• Issue: 8
• Article number: 08LT01
• Publication date: 2019-06-20
• Acceptance date: 2019-05-17
• DOI: 10.1088/1361-6471/ab227d
• EISSN: 1361-6471
• ISSN: 0954-3899
• Keywords: FFR