Benchmarking nuclear matrix elements of $0\hat{I}½{\hat{I}}^2{\hat{I}}^2$ decay with high-energy nuclear collisions

Abstract

Reducing uncertainties in the nuclear matrix elements (NMEs) remains a critical challenge in designing and interpreting experiments aimed at discovering neutrinoless double beta ($0\hat{I}½{\hat{I}}^2{\hat{I}}^2$) decay. Here, we identify a class of observables, distinct from those employed in low-energy nuclear structure applications, that are strongly correlated with the NMEs: momentum correlations among hadrons produced in high-energy nuclear collisions. Focusing on the ${}^{150}$Nd$\to$${}^{150}$Sm transition, we combine a Bayesian analysis of the structure of ${}^{150}$Nd with simulations of high-energy ${}^{150}$Nd+${}^{150}$Nd collisions. We reveal prominent correlations between the NMEs and features of the quark-gluon plasma (QGP) formed in these processes, such as spatial gradients and anisotropies, which are accessible via collective flow measurements. Our findings demonstrate collider experiments involving $0\hat{I}½{\hat{I}}^2{\hat{I}}^2$ decay candidates as a platform for benchmarking theoretical predictions of the NMEs.

8 pages, 3 figures, version to appear in Physical Review Letters