Abstract
The 2νββ decay matrix element of has been studied in a large basis shell-model space. The theoretical and experimental and spectra and their relation to 2νββ are discussed. A new empirical effective interaction is found to give the best agreement to and spectra with the effective Gamow-Teller operator σ̃t=0.77σt. The predicted =1.9× yr differs by a factor of 2 from the present experimental limit of >3.6× yr. We also compare the matrix elements obtained at various levels of the truncation in the shell-model space.
- Received 12 February 1990
DOI:https://doi.org/10.1103/PhysRevC.42.1120
©1990 American Physical Society