Nobuya Nishimura, Toshitaka Kajino, Grant J. Mathews, Shunji Nishimura, Toshio Suzuki
We investigate the effects of newly measured beta-decay half-lives on r-process nucleosynthesis. These new rates were determined by recent experiments at the radioactive isotope beam factory (RIBF) facility in the RIKEN Nishina Center. We adopt an r-process nucleosynthesis environment based on a magnetohydrodynamic supernova explosion model that includes strong magnetic fields and rapid rotation of the progenitor. A number of the new beta-decay rates are for nuclei on or near the r-process path, and hence, affect the nucleosynthesis yields and timescale of the r-process. The main effect of the newly measured beta-decay half-lives is an enhancement in the calculated abundance of isotopes with mass number A = 110 -- 120 relative to calculated abundances based upon $\beta$-decay rates estimated with the finite-range droplet mass model. This effect slightly alleviates, but does not fully explain, the tendency of $r$-process models to underproduce isotopes with A = 110 -- 120 compared to the solar-system r-process abundances.
View original:
http://arxiv.org/abs/1203.5281
No comments:
Post a Comment