Nuclear Matrix Elements for 0νββ Decay: Recent Advances

The neutrinoless double beta (0νββ) decay of atomic nuclei plays a key role in the search for massive Majorana neutrinos and their mass scale. To extract the necessary information from the measured data the nuclear‐structure effects have to be accounted for. The nuclear matrix elements (NME's) for the 0νββ decays crystallize these effects, and the calculation of these matrix elements has become of paramount importance in the community of neutrino physics. In this article we discuss the NME's for the light‐neutrino exchange mechanism, computed by using the proton‐neutron quasiparticle random‐phase approximation (pnQRPA). Recent developments in this field relate to the handling of the nucleon‐nucleon short‐range correlations in the NME's and independent experimental probes of the wave functions relevant for the NME's.