A Water v{C}erenkov Calorimeter as the Next Generation Neutrino Detector

We propose here a large homogeneous calorimeter as the next generation neutrino detector for $\nu$ factories and/or conventional $\nu$ beams. The active media is chosen to be water for obvious economical reasons. The \v Cerenkov light produced in water is sufficient to have good energy resolution, and the pattern recognition is realized by a modular water tank structure. Monte Carlo simulations demonstrate that the detector performance is excellent for identifying neutrino CC events while rejecting background events.