Mass Measurements of Neutron-Rich Gallium Isotopes Refine Production of Nuclei of the First r-Process Abundance Peak in Neutron Star Merger Calculations

2018/10/31 by M. P. Reiter, S. Ayet San Andrés, S. Nikas +33 · 1 citation
Physics and Astronomy · #nucl-ex #astro-ph.HE #nucl-th

paper · pdf · doi:10.1103/physrevc.101.025803

published as Phys. Rev. C 101, 025803 (2020)

arxiv created 2020/01/30 · arxiv updated 2020/02/19

Abstract

We report mass measurements of neutron-rich Ga isotopes ^80-85Ga with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The measurements determine the masses of ^80-83Ga in good agreement with previous measurements. The masses of ⁸⁴Ga and ⁸⁵Ga were measured for the first time. Uncertainties between 25-48 keV were reached. The new mass values reduce the nuclear uncertainties associated with the production of A ≈ 84 isotopes by the r-process for astrophysical conditions that might be consistent with a binary neutron star (BNS) merger producing a blue kilonova. Our nucleosynthesis simulations confirm that BNS merger may contribute to the first abundance peak under moderate neutron-rich conditions with electron fractions Y_e=0.35-0.38.

Cited by

• Correlated and uncorrelated Monte Carlo neutron capture rate variations in weak r-process simulations