Two-neutrino double-beta decay transition to a 2⁺excited state

Abstract

The Gamow-Teller matrix elements of 2 nu beta beta transitions to a 21+ final excited state has been calculated within the QRPA formalism for 76Ge and 136Xe. The relative stability of the calculation with respect to the particle-particle interaction strength is confirmed; on the other hand, the results are strongly dependent on the choice of the single-particle energy levels. A plausible explanation of such behaviour, originating in the interference of the individual contributions due to the third power of the energy denominator, has been proposed.

Measurement of the double beta decay half-life of Nd-150 and search for neutrinoless decay modes with the NEMO-3 detector

“…• 0νββ decay to the 2 + 1 excited state (2 + 1 RC). The mass mechanism of this decay is highly suppressed due to the nuclear angular momentum and only the right-handed current is enhanced [91].…”

The first large-scale shell-model calculation of the two-neutrino double beta decay of $^{76}$Ge to the ground and excited states in $^{76}$Se

“…In Civitarese et al [13] foundations for the multiple commutator model (MCM) were laid, and further application of the theory to many 2νββ decays was performed in Aunola et al [14]. Various higher-QRPA frameworks were applied to 2νββ decays by Bobyk et al [15], Stoica et al [16] and Raduta et al [17]. After the introduction of the renormalised QRPA (RQRPA) by Toivanen et al [18], the theory was applied to 2νββ decays by the same authors in [19] and by Schwieger et al in [20].…”

2νββ-decay to first 2+ states with partial isospin symmetry restoration from spherical QRPA calculations *

“…An empirical formula for for the double beta decay to the ground state can be found in [17]. Here, is the average mass differences between the intermediate and initial (final) nuclei.…”