Neutrino mass hierarchy determination with IceCube-PINGU

TL;DR

This paper evaluates IceCube-PINGU's potential to determine the neutrino mass hierarchy through atmospheric neutrino observations, highlighting optimization targets and synergy with other experiments.

Contribution

It provides a detailed simulation-based analysis of PINGU's sensitivity to the neutrino mass hierarchy, including systematic error impacts and optimization strategies.

Findings

90% CL to 3sigma sensitivity after three years

Synergy with NOvA enhances parameter space coverage

Low intensity neutrino beam could achieve comparable sensitivity to LBNE

Abstract

We discuss the neutrino mass hierarchy determination with atmospheric neutrinos in PINGU (Precision IceCube Next Generation Upgrade), based on a simulation with the GLoBES software including the full three flavor framework and parameter degeneracy, and we compare it to long-baseline experiment options. We demonstrate that the atmospheric mass hierarchy sensitivity depends on the achievable experiment properties and we identify the main targets for optimization, whereas the impact of a large number of tested systematical errors turns out to be small. Depending on the values of theta_23, delta, and the true hierarchy, a 90% CL to 3sigma discovery after three years of operation seems conceivable. We also emphasize the synergy with existing beam and reactor experiments, driven by NOvA, such as the complementary coverage of the parameter space. Finally, we point out that a low intensity neutrino beam with a relatively short decay pipe could be used to determine the mass hierarchy with a sensitivity comparable to the LBNE experiment irrespective of the directional resolution of the detector.