A new high-density detector for atmospheric neutrinos. Towards neutrino stoichiometry

A high-density calorimeter, consisting of magnetised iron planes interleave d by RPCs, as tracking and timing devices, is a good candidate for a next g eneration experiment on atmospheric neutrinos. With 34 kt of mass and in fo ur years of data taking, this experiment will be sensitive to nu(mu) --> nu (x) oscillation with Delta m(2) > 6 x 10(-5) and mixing near to maximal and fully cover the region of oscillation parameters suggested by Super-Kamiok ande results. Moreover, the experimental method will enable to measure the oscillation parameters from the modulation of the L/E spectrum (nu(mu) disa ppearance). For Delta m(2) > 3 x 10(-3) eV(2), this experiment can also est ablish whether the oscillation occurs into a tau or a sterile neutrino, by looking for an excess of muon-less events at high energies produced by upwa rd-going tan neutrinos (nu(tau) appearance).