Systematics of Evaluated Half-Lives of Double-Beta Decay

Abstract: A new evaluation of 2beta-decay half lives and their systematics is presented. These data extend the previous evaluation and include the analysis of all recent measurements. The nuclear matrix elements for 2beta-decay transitions in 12 nuclei have been extracted. The recommended values are compared with the large-scale shell-model, QRPA calculations, and experimental data. A T2nu 1/2 ~ 1/E8 systematic trend has been observed for recommended 128,130Te values. This trend indicates similarities for nuclear matrix elements in Te nuclei and was predicted for 2beta(2nu)-decay mode. The complete list of results is available online at http://www.nndc.bnl.gov/bbdecay/.