First application of the continuum-QRPA to the description of the double beta decay

A continuum-QRPA approach to calculation of the 2νββ2νββ- and 0νββ0νββ-amplitudes has been formulated. For 130Te, a regular suppression (about 20%) of the high-multipole contributions to the 0νββ0νββ-amplitude has been found which can be associated with additional ground state correlations appearing from the transitions to collective states in the continuum. At the same time, the total calculated 0νββ0νββ-amplitude for 130Te gets suppressed by about 20% compared to the result of the usual, discretized QRPA.