NC Coherent pi0 Production in the MiniBooNE Antineutrino Data

TL;DR

This paper reports the first measurement of neutral current coherent pi0 production in antineutrino interactions using MiniBooNE data, which is crucial for understanding backgrounds in neutrino oscillation experiments.

Contribution

It provides the first experimental measurement of NC coherent pi0 production in antineutrino data, enhancing understanding of background processes in neutrino oscillation studies.

Findings

First measurement of NC coherent pi0 production in antineutrino data.

Coherent production signature identified as forward-going pi0s.

Results improve background modeling for future oscillation experiments.

Abstract

The single largest background to future $\bar{\nu_{\mu}}\to \bar{\nu_e}$ ($\nu_\mu \to \nu_e$) oscillation searches is neutral current (NC) $\pi^{0}$ production. MiniBooNE, which began taking antineutrino data in January 2006, has the world's largest sample of reconstructed $\pi^{0}$'s produced by antineutrinos. These neutral pions are primarily produced through the $\Delta$ resonance but can also be created through ``coherent production.'' The latter process is the coherent sum of glancing scatters of antineutrinos off a neutron or proton, in which the nucleus is kept intact but a $\pi^{0}$ is created. A signature of this process is a $\pi^{0}$ which is highly forward-going. It is advantageous to study coherent production using antineutrinos rather than neutrinos because the ratio of coherent to resonant scattering is enhanced in antineutrino running. The first measurement of NC coherent $\pi^{0}$ production in the MiniBooNE antineutrino data is discussed here.