Some New Values of Atomic Masses, Principally in the Region of 82 Neutrons

Some new mass comparisons are described which lead to atomic mass values for twenty-nine stable nuclides. There is shown to be a definite mass effect associated with the closing of the 82 neutron shell and probably also with the closing of the 58 proton shell. There is evidence that the minimum of the packing fraction curve occurs at ${}_{28}{}^{}{}_{}{}^{}\mathrm{Ni}_{}^{62}{}_{}{}^{}$. Recent microwave data are used to obtain the masses of ${\mathrm{Ge}}^{74}$ and ${\mathrm{Ge}}^{76}$ from the mass spectrographically determined masses of ${\mathrm{Ge}}^{70}$ and ${\mathrm{Ge}}^{72}$.