Calculations of β-decay half-lives for neutron rich tin isotopes

Abstract

Many of the nuclei made temporarily during r-process nucleosynthesis are currently inaccessible to experiment. Their properties, however, help determine the abundances of stable elements which we observe in the solar system. Beta decay half-lives and rates are among the most important of these properties. Nuclei with 50 ≤Z≤ 56 and 82 ≤ N ≤ 88 in the π(gdsh) ⊕ν(hfpi) valence space above the 132Sn core lie on or close to the path of astrophysical r-process flow. The even-N neutron-rich Sn isotopes are the classical “waiting point” nuclei in the A=130 solar system abundance peak under typical r-process conditions. With respect to the r-process, N=86 isotope is an important waiting-point nucleus for moderate neutron densities to drive the r-process flow beyond A-130 peak. For such systems, the consideration of the three-body monopole effects is presently a relevant issue in nuclear structure calculations in order to reproduce their experimental studies. In the present work, the total β-decay half-lives and rates of the exotic Sn isotopes above the 132Sn core are calculated using monopole interaction at different temperatures. The calculation has been realized using Oxbash code in the frame work of the nuclear shell model.