Atmospheric Tau Neutrinos in a Multi-kiloton Liquid Argon Detector

TL;DR

This paper demonstrates that a large Liquid Argon detector can effectively identify atmospheric tau neutrinos, enabling new measurements of their interactions and potential new physics beyond the Standard Model.

Contribution

It introduces methods for detecting tau neutrinos in a large Liquid Argon detector and shows they can be used for fundamental physics measurements.

Findings

Approximately 30 tau neutrinos can be detected in 100 kt*yr exposure.

Detection significance exceeds 4 sigma.

Enables measurements of tau neutrino cross-sections and shape parameters.

Abstract

An ultra-large Liquid Argon Time Projection Chamber-based neutrino detector will have the uncommon ability to detect atmospheric tau neutrino events. This paper discusses the most promising modes for identifying charged current tau neutrino interactions, and shows that, with simple kinematic cuts, ~30 tau neutrinos can be isolated in a 100 kt*yr exposure, with greater than 4 sigma significance. This sample is sufficient to perform flux-averaged total cross-section and cross-section shape parameterization measurements -- the first steps toward using tau neutrinos to search for physics beyond the Standard Model.