Synthesis of the heavy elements.

The processes of explosive charged-particle nucleosynthesis and neutron capture production of heavy nuclei in the ejection of core material in supernova events and in stellar interiors, respectively, are discussed. The explosive processes are characterized by the peak shock temperatures to which the matter present is exposed, and C, O, and Si burning in the supernova environment is noted to be a process independent of stellar models, and produce elements ranging from Fe-Ni. Attention is given to models for environment which lead to r-process nucleosynthesis, including the expansion of neutronized matter and shock processing of He layers resulting in a neutron-rich environment. He-burning cores of massive stars and convective He-burning shells of thermally pulsing stars are regions of s-process events, and are limited by the necessary 300-350 million K temperature requirements and the solar-system magnitude of the modeled event.