The road from QCD to nuclear double-beta decays

  • April 12, 2018, 2:30 pm US/Central
  • Wilson Hall, Curia II
  • Zohreh Davoudi, University of Maryland
  • Ciaran
  • Inspires
  • Slides

Neutrinoless double-beta decay, as a lepton-number violating process, has been the focus of numerous experimental and theoretical investigations in recent years. While it proves that neutrinos are Majorana particles once observed, the underlying new physics responsible for this process can only be constrained if the theoretical predictions of the rate are substantially refined. This talk demonstrates the roadmap in connecting the underlying high-scale theory to the corresponding nuclear matrix elements, focusing mainly on the nucleonic matrix elements in the simplest extension of Standard Model in which a light Majorana neutrino is mediating the process. The role of lattice QCD and effective field theory in this program, in particular, the prospect of a direct matching of the nn to pp amplitude to lattice QCD will be discussed. As a first step towards this goal, the results of the first lattice QCD calculation of the relevant matrix element for neutrinofull double-beta decay will be presented, albeit with unphysical quark masses, along with important lessons that could impact the calculations of nuclear matrix elements involved in double-beta decays of heavier isotopes.