CP violation and mass hierarchy with a combined sensitivity of T2K-II, NO$\nu$A and JUNO

Recent T2K data indicates a CP violation in the neutrino oscillations and mildly favours the normal neutrino mass hierarchy. This work explores the physics potentials with a combined sensitivity of T2K-II, NO$\nu$A, and JUNO experiments. T2K-II, a proposed run extension up to 2026 by T2K collaboration, is sensitive to CP violation at a level of $3\sigma$ or higher if ${\delta }_{CP}\sim -\pi /2$. NO$\nu$A is sensitive to both mass hierarchies and CP violation. JUNO, expected to take data from 2021, has $3\sigma$ or higher sensitivity to the mass hierarchy and 1% or better precision measurement of solar parameters and atmospheric mass splitting. A combined sensitivity of the three experiments allows us to achieve the most sensitivity to the CP violation and mass hierarchy before 2027 when Hyper-Kamiokande and DUNE are expected to start.