The Effects of Nuclear Stability on the Formation of the Chemical Elements

Nuclear stability considerations are applied to the neutron capture theory of the formation of the chemical elements. It is shown that the matter density during the time of formation must have remained within the limits 10^-1 g/cm³ and 10^-11 g/cm³. The nuclei were probably formed with some neutron excess so that both neutron capture and β-decay were effective in determining relative abundances. The claim of formation followed a path such that the β-decay and capture probabilities were approximately equal. The abundance of nuclei of even atomic weight over those of odd atomic weight can be explained from the general features of the nuclear energy surface, regardless of the neutron excess at the instant of formation.