Enhancing the hierarchy and octant sensitivity of ESS νSB in conjunction with T2K, NO νA and ICAL@INO

摘要

A bstract The main aim of the ESS ν SB proposal is the discovery of the leptonic CP phase δ ~(CP)with a high significance (5 σ for 50% values of δ ~(CP)) by utilizing the physics at the second oscillation maxima of the P ~( μe )channel. It can achieve 3 σ sensitivity to hierarchy for all values of δ ~(CP). In this work, we concentrate on the hierarchy and octant sensitivity of the ESS ν SB experiment. We show that combining the ESS ν SB experiment with the atmospheric neutrino data from the proposed India-based Neutrino Observatory (INO) experiment can result in an increased sensitivity to mass hierarchy. In addition, we also combine the results from the ongoing experiments T2K and NO ν a assuming their full run-time and present the combined sensitivity of ESS ν SB + ICAL@INO + T2K + NO ν A. We show that while by itself ESSνSB can have up to 3 σ hierarchy sensitivity, the combination of all the experiments can give up to 5 σ sensitivity depending on the true hierarchy-octant combination. The octant sensitivity of ESS ν SB is low by itself. However the combined sensitivity of all the above experiments can give up to 3 σ sensitivity depending on the choice of true hierarchy and octant. We discuss the various degeneracies and the synergies that lead to the enhanced sensitivity when combining different experimental data.