PT Journal
AU T2K Collaboration (Abe, Kea
   Antonova, M
   Cervera-Villanueva, A
   Fernandez, P
   Izmaylov, A
   Novella, P
TI Search for neutral-current induced single photon production at the ND280 near detector in T2K
SO Journal of Physics G
JI J. Phys. G
PY 2019
BP 08LT01
EP 16pp
VL 46
IS 8
DI 10.1088/1361-6471/ab227d
LA English
DE T2K; neutrino; neutrino oscillation; neutrino interaction; Mini-BooNE; CP violation
AB Neutrino neutral-current (NC) induced single photon production is a sub-leading 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 fine-grained 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 x 10(20) 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 x 10(-38) cm(2) (90% C.L.) per nucleon, using the J-PARC off-axis neutrino beam with an average energy of < E-v > similar to 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.
ER