Study of the intrinsic electron neutrino component in the T2K neutrino beam with the near detector, ND280

TL;DR

This paper analyzes the intrinsic electron neutrino component in the T2K beam using ND280 data, aiming to improve background constraints and measure cross sections relevant for neutrino oscillation studies.

Contribution

It introduces a method to select and analyze electron neutrino interactions in the T2K near detector, enhancing background understanding and cross section measurements.

Findings

Improved constraint on intrinsic electron neutrino background.

Measurement of CC0pi electron neutrino cross section.

Enhanced understanding of neutrino interaction channels.

Abstract

T2K is an off-axis long baseline neutrino oscillation experiment optimised to measure theta13 and deltaCP using a muon neutrino beam. The most sensitive mode is to look for electron neutrino appearance, and the dominant background for such measurements is the intrinsic electron neutrino component in the beam itself. A selection is made using data from the off-axis near detector (ND280) to detect charged current (CC) electron neutrino interactions; these are split into events with no pions in the final state (nue CC0pi) and the remaining CC interactions (nue CCother). This strategy will both improve the constraint of the intrinsic background by this analysis and allow a measurement of the CC0pi cross section