$\gamma \gamma$ decay as a probe of neutrinoless $\beta \beta$ decay nuclear matrix elements

B. Romeo, J. Menéndez, C. Peña

We study double gamma ($\gamma \gamma$) decay nuclear matrix elements (NMEs) for a wide range of nuclei from titanium to xenon, and explore their relation to neutrinoless double-beta ($0\nu \beta \beta$)…