Establishing neutrino mass hierarchy and CP violation by two identical detectors with different baselines using the J-PARC neutrino beam

We discuss how and to what extent one can determine the neutrino mass hierarchy, normal or inverted, and at the same time uncover CP violation in the lepton sector by using two identical detectors with different baselines in neutrino oscillation experiments using low energy superbeam from the J-PARC facility.