2025/08/27 by Nomura, Kosuke
#FOS: Physical sciences #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.2508.20323
Mixing and coexistence of intrinsic nuclear shapes play an important role to determine the low-energy structure of heavy nuclei, and are expected to affect nuclear matrix elements (NMEs) of neutrinoless double beta (0νββ) decay. This problem is addressed in the interacting boson model with configuration mixing that is formulated by using the nuclear energy density functional theory. It is shown that significant amounts of mixing of normal and deformed intruder configurations are present in the ground and excited 0+ states in the even-even nuclei that are parent or daughter nuclei of the 0νββ decay. An illustrative application to the 0νββ decays of 76Ge, 96Zr, 100Mo, 116Cd, and 150Nd shows that the inclusion of the configuration mixing reduces the NMEs for most of the 0+1 → 0+1 0νββ decays.