Atomic masses of intermediate-mass neutron-deficient nuclei with relative uncertainty down to 35-ppb via multireflection time-of-flight mass spectrograph

摘要

High-precision mass measurements of (63)cu, (64-66)zn, Ga-65, Ge65-67, As-67, Br-78,Br-81, Rb-80, and Sr-79 were performed utilizing a multireflection time-of-flight mass spectrograph combined with the gas-filled recoil ion separator GARIS-II. In the case of Ga-65, a mass uncertainty of 2.1 keV, corresponding to a relative precision of delta m/m = 3.5 x 10(-8), was obtained and the mass value is in excellent agreement with the 2016 Atomic Mass Evaluation. For Ge-67 and Br-81, where masses were previously deduced through indirect measurements, discrepancies with literature values were found. The feasibility of using this device for mass measurements of more neutron-deficient nuclei, which have significant impact on the rp-process pathway, is discussed. (C) 2018 Elsevier B.V. All rights reserved.