Neutrinoless $\beta\beta$ decay nuclear matrix elements complete up to
N$^2$LO in heavy nuclei
Neutrinoless $\beta\beta$ decay nuclear matrix elements complete up to
N$^2$LO in heavy nuclei
We evaluate all nuclear matrix elements (NMEs) up to next-to-next-to leading order (N$^2$LO) in chiral effective field theory ($\chi$EFT) for the neutrinoless double-beta ($0\nu\beta\beta$) decay of the nuclei most relevant for experiments, including $^{76}$Ge, $^{100}$Mo, and $^{136}$Xe. We use the proton-neutron quasiparticle random-phase approximation (pnQRPA) and the nuclear shell model …