Neutrino Oscillations With A Next Generation Liquid Argon TPC Detector in Kamioka or Korea Along The J-PARC Neutrino Beam

The ``baseline setup'' for a possible, beyond T2K, next generation long baseline experiment along the J-PARC neutrino beam produced at Tokai, assumes two very large deep-underground Water Cerenkov imaging detectors of about 300 kton fiducial each, located one in Korea and the other in Kamioka but at the same off-axis angle. In this paper, we consider the physics performance of a similar setup but with a single and smaller, far detector, possibly at shallow depth, composed of a 100 kton next generation liquid Argon Time Projection Chamber. The potential location of the detector could be in the Kamioka area ($L\sim 295$ km) or on the Eastern Korean coast ($L\sim 1025$ km), depending on the results of the T2K experiment. In Korea the off-axis angle could be either $2.5^{o} \sim 3^{o}$ as in SuperKamiokande, or $\sim 1^{o}$ as to offer pseudo-wide-band beam conditions.