1999/04/23 by P. Vogel, Petr Vogel, Vogel, Petr
Physics and Astronomy · #FOS: Physical sciences #Neutrino Physics Research #Nuclear Theory (nucl-th) #Nuclear physics research studies #Quantum, superfluid, helium dynamics #nucl-th
paper · pdf · doi:10.48550/arxiv.nucl-th/9904065
Invited talk at the Workshop on Beta-Decay, Strasbourg, France, March 1999
arxiv created 1999/04/23 · openalex publication_date 1999/04/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Study of the neutrinoless ββ decay allows us to put a stringent limit on the effective neutrino Majorana mass, a quantity of fundamental importance. To test our ability to evaluate the nuclear matrix elements that govern the decay rate, it is desirable to be able to describe the allowed two-neutrino decay. It is argued that only low-lying virtual intermediate states are important for that process, and thus it appears that the large-scale shell model evaluation, free from the various difficulties of QRPA, is the preferred method. In the 0ν decay, it is shown that there is a substantial cancellation between the paired and broken pair pieces of the nuclear wave function. Thus, despite the popular claim to the contrary, one expects that the 0ν rate is also sensitive to the details of nuclear structure. This is reflected in the spread of the theoretical values, leading to the uncertainty of about factor 2-3 in the deduced limit. Finally, brief comment about the 0ν decay with the exchange of a very heavy neutrino are made.