A separation method of 0 nu- and 2 nu-events in double beta decay experiments with DCBA

A detector called Drift Chamber Beta-ray Analyzer (DCBA) will provide momen tum information of each beta-ray in double beta decay. The DCBA is expected to have good capabilities for particle identification, detection efficienc y, background elimination and decay-source integration. Under the assumptio n of mass mechanism dominance in neutrinoless double beta decay, a simulati on study shows that a combination method using both sum and single-energy d istributions of double beta decay events can separate 0 nu- and 2 nu-events down to 0.05 eV of the effective neutrino mass with the help of a calculat ed nuclear matrix element, even though the DCBA has relatively poor energy resolution. (C) 2000 Elsevier Science B.V. All rights reserved.