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

Abstract

A continuum-QRPA approach to calculation of the $2\nu \beta \beta$- and $0\nu \beta \beta$-amplitudes has been formulated. For ${}^{130}$Te a regular suppression (about 20%) of the high-multipole contributions to the $0\nu \beta \beta$-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 $0\nu \beta \beta$-amplitude for ${}^{130}$Te gets suppressed by about 20% as compared to the result of the usual, discretized, QRPA.

Comments: 8 pages, 2 figures. Proceedings of the 27th Int. School on Nuclear Physics "Neutrinos in Cosmology, in Astro, Particle and Nuclear Physics", Erice, Italy, Sept. 16-24, 2005. To appear in Prog.Part.Nucl.Phys