Effects of orbital occupancies and spin–orbit partners II: 0νββ decays of 76Ge, 82Se and 136Xe to first excited 0+ states

The neutrinoless double beta (0νββ) decays of 76Ge, 82Se and 136Xe to the first excited 0+ states () in 76Se, 82Kr and 136Ba are studied in calculations using different sizes of the single-particle model spaces and different occupancies of the individual orbits. This is a continuation of a similar study [J. Suhonen, O. Civitarese, Effects of orbital occupancies and spin–orbit partners on 0νββ-decay rates, Nucl. Phys. A 847 (2010) 207–232] of the 0νββ decays of 76Ge, 82Se, 128Te, 130Te and 136Xe to the ground states of 76Se, 82Kr, 128Xe, 130Xe and 136Ba. The nuclear matrix elements and half-lives of the decays to the states are calculated by the use of the multiple-commutator model with effective, G-matrix-derived nuclear forces. Interestingly, the basic features of the ground-state and excited-state decays are found to be quite different. The half-lives of the excited-state transitions are suppressed by at least one order of magnitude relative to the ground-state transitions.