Nucleosynthesis is the creation of atomic nuclei, i.e., the creation of elements. Types include:
Stellar Nucleosynthesis - Proton-Proton Chain, Triple Alpha Process, CNO Cycle, S-Process, R-Process (types of Neutron Capture), rp-process, Photodisintegration, Carbon (C) Burning (if 6×108 K, producing oxygen Neon, Sodium, and Magnesium), and Oxygen (O) Burning (if 109 K, producing magnesium, Silicon (Si), Phosphorus, and Sulfur (S)).
Supernova Nucleosynthesis - processes within supernovae (SN) such as the r-process or rp-process.
Cosmic Ray Spallation - reduction of nuclei through impact with Cosmic Rays.
Stellar Age Determination