Relative Cross Section Measurment of Inclusive Charged Current Multiple Pion Production to Inclusive Charged Current from Muon Neutrinos at the Near Detector of the T2K Experiment

Abstract

The Tokai-to-Kamiokande (T2K) experiment is an off-axis, long baseline neutrino oscillation experiment based in Japan. One of the largest sources of systematic uncertainty in the oscillation analysis is the uncertainty on neutrino cross sections. In this thesis, we use the π<super>0</super> detector (P0D) of the T2K Near Detector to measure one cross section of muon neutrinos. The P0D is a scintillator based detector with a precision water target which allows for a measurement with water and without water. In particular, we measured the relative cross section of charged current multiple pion production to inclusive charged current production. The analysis is performed with a multi-variate template fit using two Monte Carlo neutrino generators, NEUT and GENIE. The relative ratio for NEUT(GENIE) is 0.126±0.024+0.022-0.021(0.100±0.018+0.018-0.017) for the Water-In configuration and 0.104±0.029+0.030-0.035(0.121±0.021+0.034-0.036) for the Water-Out configuration. The prospects for a precision water cross section measurement are also discussed.