Study of the Neutral-Current interactions with production of neutral pions in the T2K off-axis near detector

Abstract

This analysis aims to study inclusive neutrino-induced Neutral Current (NC) interactions that produce at least one neutral pion ($π^0$) in the final state (incNC$π^0$ ) in the T2K off-axis near detector ND280. The motivation for this study is to better understand/eliminate the background to electron neutrino appearance analyzed at the far detector Super-Kamiokande. As $π^0$ decays are background to the appearance search, a good knowledge of both inclusive and exclusive neutrino interaction cross sections are key to improving associated systematic uncertainties in T2K oscillation analyses. Results from this study can be compared to a number of Monte Carlo samples produced using different neutrino interaction generators. This could yield information about models of neutrino-nucleon interactions. Further comparisons can be made with the incCC$π^0$ sample already obtained from a T2K near detector analysis. In this poster, the selection criteria used to collect inclusive neutral current neutrino interactions on plastic scintillator (CH) with at least one $π^0$ in the final state will be presented, including a discussion of how selection criteria were improved. I will also discuss the changes in the selections, including use of a fitting method to improve measurement of the incNC$π^0$ interaction rate.

Talk presented at NuPhys2017 (London, 20-22 December 2017). 5 pages, LaTeX, 2 png figures