Search for Majorana neutrinos

Abstract

AbstractWhether there exist elementary particles having Majorana nature is a fundamental open question that has persisted since the 1930s. The only practical experiments to test the Majorana nature of neutrinos is the search for neutrinoless double-beta decay, which has been a major challenge for nuclear and particle physicists. In the 2000s, a number of experiments using advanced technologies were planned, some of which have already achieved significant improvements in the search sensitivity. In this article, the current status of the neutrinoless double-beta decay searches is summarized, reviewing the progress of KamLAND-Zen, which recorded the world’s best sensitivity in the effective Majorana neutrino mass limit.