COBRA — double beta decay searches using CdTe detectors

A new approach (called COBRA) for investigating double beta decay using CdTe semiconductor detectors is proposed. This will allow simultaneous measurements of 5ß-ß-- and 4ß+ß+-emitters at once. Half-life limits for neutrinoless double beta decay of 116Cd and 130Te can be improved by more than one order of magnitude and sensitivities on the effective Majorana neutrino mass of less than 1 eV can be obtained. Furthermore, for the first time a realistic chance of observing double electron capture processes exists. Additional searches for rare processes like the 4-fold forbidden 113Cd ß-decay, the electron capture of 123Te and dark matter detection can be performed. The achievable limits are evaluated for 10 kg of such detectors and can be scaled accordingly towards higher masses because of the modular design of the proposed experiment.