Neutrino Flavor Ratio on Earth and at Astrophysical Sources

TL;DR

This paper discusses methods to reconstruct neutrino flavor ratios at astrophysical sources and emphasizes the need for precise flux ratio measurements to distinguish different source types with high confidence.

Contribution

It introduces a reconstruction approach for neutrino flavor ratios and specifies the measurement accuracy required to differentiate source types.

Findings

Achieving better than 10% accuracy in flux ratios is necessary.

Distinguishing pion and muon-damped sources at 3σ level is feasible with current measurement precision.

Flux ratios R and S are key parameters for source identification.

Abstract

We present the reconstruction of neutrino flavor ratios at astrophysical sources. For distinguishing the pion source and the muon-damped source to the 3$\sigma$ level, the neutrino flux ratios, $R\equiv\phi(\nu_\mu)/(\phi(\nu_e)+\phi(\nu_\tau))$ and $S\equiv\phi(\nu_e)/\phi(\nu_\tau)$, need to be measured in accuracies better than 10%.