Enhancing the sensitivity to neutrino oscillation parameters using synergy between T2K, NO$\nu$A and JUNO

Abstract

We study the impact of combining the present NO$\nu$A and T2K data with simulated data from the JUNO experiment on the determination of the leptonic CP phase and the neutrino mass hierarchy. The current NO$\nu$A data exhibit a hierarchy--${\delta }_{\mathrm{CP}}$ degeneracy, admitting both normal hierarchy (NH) with ${\delta }_{\mathrm{CP}}\in [0,180^{\circ }]$, and inverted hierarchy (IH) with ${\delta }_{\mathrm{CP}}\in [180^{\circ },360^{\circ }]$ solutions at comparable significance, while T2K prefers ${\delta }_{\mathrm{CP}}\simeq 270^{\circ }$ for both hierarchies, leading to a $2\sigma$ tension between the two experiments for normal hierarchy. Using detailed GLoBES simulations, we show that future JUNO data with excellent hierarchy sensitivity, can lift the hierarchy--${\delta }_{\mathrm{CP}}$ degeneracy in NO$\nu$A and strengthen the hierarchy reach of T2K in spite of having no ${\delta }_{\mathrm{CP}}$ sensitivity. Allowing the hierarchy to be a free parameter in the fit, if the true ordering is IH, JUNO aligns the NO$\nu$A and T2K allowed regions and resolves their present tension; if NH is true, the tension continues to persist. We also show that JUNO's precise measurement of $|{\Delta }_{31}|$ leads to improved constraints on ${\sin }^2{\theta }_{23}$ and ${\delta }_{\mathrm{CP}}$ for normal mass hierarchy in NO$\nu$A even though JUNO itself is insensitive to these parameters. Finally, updated solar parameter measurements from JUNO's first data release further enhance the combined precision. Our results demonstrate that JUNO plays a crucial synergistic role in the global neutrino oscillation programme, enabling a more robust determination of the mass ordering and improving the sensitivity to the CP phase when combined with long-baseline data.

37 pages, 18 figures, 3 tables, and 3 appendices. Matches the version published in JHEP

References in corpus (36)

• Neutrino Physics with JUNO
• Global analysis of three-flavour neutrino oscillations: synergies and tensions in the determination of theta_23, delta_CP, and the mass ordering
• Simulation of long-baseline neutrino oscillation experiments with GLoBES
• New features in the simulation of neutrino oscillation experiments with GLoBES 3.0
• Golden measurements at a neutrino factory
• Breaking Eight-fold Degeneracies in Neutrino CP Violation, Mixing, and Mass Hierarchy
• NuFit-6.0: Updated global analysis of three-flavor neutrino oscillations
• Solar and Atmospheric Neutrino Oscillations and Lepton Flavor Violation in Supersymmetric Models with Right-handed Neutrinos
• Exploring Neutrino Mixing with Low Energy Superbeams
• On the measurement of leptonic CP violation
• Tests of three-flavor mixing in long-baseline neutrino oscillation experiments
• The LMA MSW Solution of the Solar Neutrino Problem, Inverted Neutrino Mass Hierarchy and Reactor Neutrino Experiments
• Neutrino Propagation in Matter
• Precision Neutrino Oscillation Physics with an Intermediate Baseline Reactor Neutrino Experiment
• Superbeams plus Neutrino Factory: the golden path to leptonic CP violation
• CP-Violating Neutrino Non-Standard Interactions in Long-Baseline-Accelerator Data
• Resolving Eight-Fold Neutrino Parameter Degeneracy by Two Identical Detectors with Different Baselines
• Resolving the octant of theta23 with T2K and NOvA
• Non-standard neutrino interactions as a solution to the NO$\nu$A and T2K discrepancy
• Neutrino mass hierarchy and electron neutrino oscillation parameters with one hundred thousand reactor events
• Exploring Leptonic CP Violation by Reactor and Neutrino Superbeam Experiments
• Getting the best out of T2K and NOvA
• Exploring the sensitivity of current and future experiments to ${\theta }_{\odot }$
• Potential of optimized NOvA for large theta(13) & combined performance with a LArTPC & T2K
• Untangling CP Violation and the Mass Hierarchy in Long Baseline Experiments
• New look at the degeneracies in the neutrino oscillation parameters, and their resolution by T2K, NO$\nu$A and ICAL
• Terrestrial matter effects on reactor antineutrino oscillations at JUNO or RENO-50: how small is small?
• The physics of antineutrinos in DUNE and determination of octant and ${\delta }_{CP}$
• Why matter effects matter for JUNO
• Physics potentials with a combined sensitivity of T2K-II, NO$\nu$A extension and JUNO
• Solving the octant degeneracy with the Silver channel
• A review of the tension between the T2K and NO$\nu$A appearance data and hints to new physics
• The need for an early anti-neutrino run of NOvA
• Octant Degeneracy, Quadrant of leptonic CPV phase at Long Baseline Neutrino Experiments and Baryogenesis
• Understanding the degeneracies in NO$\nu$A data
• Update on non-unitary mixing in the recent NO$\nu$A and T2K data