T2K is a long baseline neutrino experiment located in Japan, which aims to measure neutrino oscillations. An accelerator is used to produce neutrinos, that are then detected in a near detector complex and a far detector (Super-Kamiokande). The muon neutrino charged current interactions in the near detector (ND280) are used to predict the event rate at the far detector and better constrain the cross section parameters, which are dominant in the oscillation analysis together with the flux uncertainty.
We present the study of charged current interactions on carbon with a single positively charged pion in the final state at the T2K off-axis near detector. This signal constitutes the main background for the muon neutrino disappearance measurement when the charged pion is not observed and its precise knowledge is relevant for all current and planned neutrino oscillation experiments. Single pion production is sensitive mainly to resonant processes but also to non-resonant contributions as well as coherent pion production. Adler Angles are observables carrying information about the polarization of the Delta resonance and the interference with the non-resonant single pion production. They were measured with limited statistics in bubble chamber experiments but it is possible to measure the Adler angles for single charged pion production in neutrino interactions with heavy nuclei as the target.
Cosimo Nigro, César Jesús-Valls, Jan Ollé