Speaker
Description
The observation of neutrino oscillations and therefore non-zero neutrino masses provides a clear signature for physics beyond the Standard Model. However, the origin of these masses and whether neutrinos are Dirac or Majorana particles remains an open question. Searches for neutrinoless double beta decay ($0\nu\beta\beta$), a signature of Majorana neutrinos and new physics, is a focus of the current experimental program. The decay rate depends on nuclear matrix elements (NME) of the transition, which cannot be measured and must be determined theoretically. Precise determinations of these NMEs allows for a better comparison of experimental data to different neutrino model predictions. We calculate three-nucleon $0\nu\beta\beta$ transition operators induced from the light-neutrino-exchange mechanism within the framework of chiral effective field theory. We include $\Delta$ degrees of freedom and include contributions up to next-to-next-to leading order (N2LO).
