Measurements of $\pi^{\pm}$ differential yields from the surface of the T2K replica target for incoming 31 GeV/c protons with the NA61/SHINE spectrometer at the CERN SPS

TL;DR

This paper reports detailed measurements of charged pion yields from a T2K replica target using the NA61/SHINE detector, aiming to improve neutrino flux predictions for the T2K experiment.

Contribution

It provides fully-corrected differential yields of $^\u00b1$-mesons from the target surface, along with a strategy to incorporate these results into T2K neutrino flux models.

Findings

Differential yields of $^\u00b1$-mesons measured at 31 GeV/c proton energy.

Analysis techniques for long-target neutrino flux predictions developed.

Uncertainty propagation to neutrino flux demonstrated.

Abstract

Measurements of particle emission from a replica of the T2K 90 cm-long carbon target were performed in the NA61/SHINE experiment at CERN SPS, using data collected during a high-statistics run in 2009. An efficient use of the long-target measurements for neutrino flux predictions in T2K requires dedicated reconstruction and analysis techniques. Fully-corrected differential yields of $\pi^\pm$-mesons from the surface of the T2K replica target for incoming 31 GeV/c protons are presented. A possible strategy to implement these results into the T2K neutrino beam predictions is discussed and the propagation of the uncertainties of these results to the final neutrino flux is performed.