The creation of the first r-process peak elements; effects of beta decay rates and nuclear masses

Abstract

We present a study exploring the impact of nuclear masses and beta-decay rates on the creation of the first r-process peak. We explore a large range of conditions, matching the recent observations of the blue kilonova, and determine the appropriate conditions for creating the first r-process peak elements. We use the nuclear reaction code TALYS to calculate (n, γ) reaction rates, and the GSINet code for reaction network calculations. We conclude that an electron fraction between 0.35 and 0.4 and entropy of (10-20) k<sup > B<sub>/baryon should be considered to match the r-process residuals. Furthermore, we explore the impact of masses and beta-decays on the production of A « 80 nuclei.