Weak non-mesonic decays of Λ-hypernuclei

Abstract

We review the current status of studies of weak decays of Λ-hypernuclei. Both experimental and theoretical aspects are reviewed, with emphasis on the weak non-mesonic decays. Experimental results obtained during the last thirty years are described and discussed in detail. The current theoretical understanding of the subject is analysed, following the various approaches in the pertinent literature. For the most part, available treatments are based on the two-body Λ+N→N+N weak interaction as the underlying non-mesonic decay mechanism. Starting with the phenomenological approach of Dalitz et al. , and continuing with a description of microscopic models suggested for the Λ+N→N+N interaction, we review over thirty years of theoretical efforts. The implications of recent studies of weak decays of hypernuclei at Brookhaven where data for, e.g., Λ 12 C and Λ 5 He have been obtained, are discussed. The need for new and improved measurements is pointed out. Future prospects and selected opportunities for new and further studies are described.