Some atoms are stable, while others seem to fall apart. Lead-208 will probably last forever, while the synthetic isotope technetium-99 exists for just hours. The difference lies in the structure of ...

Atomic nuclei are often described as orderly systems. Certain numbers of protons or neutrons, called magic numbers, usually produce especially stable and spherical nuclei.

The red ball, blue star and black square represent the corresponding results of Rn, Ra and Th isotopes, respectively. In the shell model, the neutron number N=126 is regarded as a neutron magic number ...