Average and recommended half-life values for two-neutrino double-beta decay: Upgrade ’05

All existing “positive” results on two-neutrino double-beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of ⁴⁸Ca, ⁷⁶Ge, ⁸²Se, ⁹⁶Zr, ¹⁰⁰Mo, ¹⁰⁰Mo−¹⁰⁰Ru(0 ₁ ⁺ ), ¹¹⁶Cd, ¹⁵⁰Nd, ¹⁵⁰Nd− ¹⁵⁰Sm(0 ₁ ⁺ ) and ²³⁸U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of ¹²⁸Te, ¹³⁰Te, and ¹³⁰Ba are proposed. We recommend the use of these results as presently the most precise and reliable values for half-lives. Presented by A.S. Barabash at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece, September 26–29, 2005.