We report mass measurements of neutron-rich Ga isotopes Ga80-85 with TRIUMF's Ion Trap for Atomic and Nuclear science. The measurements determine the masses of Ga80-83 in good agreement with previous measurements. The masses of Ga84 and Ga85 were measured for the first time. Uncertainties between 25 and 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 Ye=0.35-0.38.
ASJC Scopus subject areas
- Nuclear and High Energy Physics