The physics impact of proton track identification in future megaton-scale water Cherenkov detectors

TL;DR

This paper explores how proton Cherenkov ring identification in future large-scale water Cherenkov detectors can enhance neutrino event reconstruction, improve energy resolution, and aid in sterile neutrino searches.

Contribution

It demonstrates that proton ring identification enables full neutrino kinematic reconstruction and better neutrino-antineutrino discrimination in megaton-scale water Cherenkov detectors.

Findings

Proton identification improves energy resolution.

Enhanced neutrino-antineutrino tagging capabilities.

Feasible beam parameters for effective proton ring detection.

Abstract

In this paper, we investigate the impact in future megaton-scale water Cherenkov detectors of identifying proton Cherenkov rings. We estimate the expected event rates for detected neutral current and charged current quasi-elastic neutrino interactions from atmospheric neutrinos in a megaton-scale Super-Kamiokande-like detector with both 40% and 20% photo-cathode coverage. With this sample we examine the prospects for measuring the neutrino oscillation pattern, and searching for sterile neutrinos. We also determine the size of selected charged current quasi-elastic samples in a 300-kton fiducial volume Super-Kamiokande-like detector from examples of both conventional super-beams and beta-beams proposed in the literature. With these samples, it is shown that full kinematic neutrino reconstruction using the outgoing proton can improve the reconstructed energy resolution, and give good neutrino versus anti-neutrino tagging capabilities, adding important capabilities to water Cherenkov detectors in future projects. We determine the beam parameters necessary to make use of this technique and present distributions of neutrino and anti-neutrino selection efficiencies.