High sensitivity 2 beta decay study of Cd-116 and Mo-100 with the BOREXINOcounting test facility (CAMEO project)

The unique features (super-low background and large sensitive volume) of th e CTF and BOREXINO set ups are used in the CAMEO project for a high sensiti vity study of Mo-100 and Cd-116 neutrinoless 2 beta decay. Pilot measuremen ts with Cd-116 and Monte Carlo simulations show that the sensitivity of the CAMEO experiment (in terms of the half-life limit for 0v2 beta decay) is a pproximate to4 x 10(24) yr With a 1 kg source of Mo-100 and approximate to 10(26) yr with approximate to 100 kg of enriched (CdWO4)-Cd-116 crystals pl aced in the liquid scintillator of the CTF. The last value corresponds to a limit on the neutrino mass of m(v) less than or equal to 0.06 eV. Similarl y With 1000 kg of (CdWO4)-Cd-116 crystals located in the BOREXINO apparatus the neutrino mass limit can be pushed down to m(v) less than or equal to 0 .02 eV.