Double beta decay

摘要

The subjects of the two-neutrino (2) and neutrinoless double beta (0) decays are introduced. The main theoretical and experimental issues related to the double beta decay are discussed. It is stressed that the study of the 0 decay is the most important source of information about the Majorana nature of neutrinos. In addition, the 0-decay half-life can constrain the absolute neutrino mass-scale and the neutrino mass pattern. Morever, the Majorana CP-violating phases, which might be responsible for the matter asymmetry of the Universe, could be deduced from the measured 0-decay rate, once this process will be observed. One can conclude that the double beta decay is an important process for the fields of nuclear physics, particle physics, astrophysics and cosmology. ?2007 American Institute of Physics.