Exploring the three flavor effects with future superbeams using liquid argon detectors

TL;DR

This paper compares the potential of future superbeam experiments LBNE and LBNO with liquid argon detectors to resolve neutrino mass hierarchy, octant, and CP violation, highlighting significant improvements with combined data.

Contribution

It provides a detailed comparative analysis of LBNE and LBNO's capabilities in neutrino physics, emphasizing the impact of combining data from T2K and NOvA.

Findings

LBNO can discover mass hierarchy with >7 sigma significance.

LBNE10 combined with T2K and NOvA achieves 3 sigma hierarchy discrimination.

Both experiments can establish leptonic CP violation for about 50% of deltaCP values.

Abstract

Recent measurement of a moderately large value of theta13 signifies an important breakthrough in establishing the standard three flavor oscillation picture of neutrinos. It has provided an opportunity to explore the sub-dominant three flavor effects in present and future long-baseline experiments. In this paper, we perform a comparative study of the physics reach of two future superbeam facilities, LBNE and LBNO in their first phases of run, to resolve the issues of neutrino mass hierarchy, octant of theta23, and leptonic CP violation. We also find that the sensitivity of these future facilities can be improved significantly by adding the projected data from T2K and NOvA. Stand-alone LBNO setup with a 10 kt detector has a mass hierarchy discovery reach of more than 7 sigma, for the lowest allowed value of sin^2theta23(true) = 0.34. This result is valid for any choice of true deltaCP and hierarchy. LBNE10, in combination with T2K and NOvA, can achieve 3 sigma hierarchy discrimination for any choice of deltaCP, sin^2theta23, and hierarchy. The same combination can provide a 3 sigma octant resolution for sin^2theta23(true) leq 0.44 or for sin^2theta23(true) geq 0.58 for all values of deltaCP(true). LBNO can give similar results with 10 kt detector mass. In their first phases, both LBNE10 and LBNO with 20 kt detector can establish leptonic CP violation for around 50% values of true deltaCP at 2 sigma confidence level. In case of LBNE10, CP coverage at 3 sigma can be enhanced from 3% to 43% by combining T2K and NOvA data, assuming sin^2theta23(true) = 0.5. For LBNO setup, CP violation discovery at 3 sigma is possible for 46% values of true deltaCP if we add the data from T2K and NOvA.