LAGUNA and LAGUNA–LBNO: Future megaton neutrino detectors in Europe

The FP7 Design Studies LAGUNA (Large Apparatus studying Grand Unification and Neutrino Astrophysics) and LAGUNA–LBNO (Large Apparatus studying Grand Unification and Neutrino Astrophysics and Long Baseline Neutrino Oscillations) are studying Pan-European research infrastructures in deep underground cavities able to host a very large multipurpose next-generation neutrino observatory. These future megaton scale detectors are dedicated to nucleon decay, neutrinos from supernovæ, solar and atmospheric neutrinos, as well as neutrinos from a future Super-Beam or β - Beam to measure the mixing angle θ 13 , the CP violating phase δ and the mass hierarchy.