Supernova Nucleosynthesis - Elements Fused

Elements Fused

In nuclear fusion processes during stellar nucleosynthesis, the maximum weight for an element fused is that of iron, reaching an isotope with an atomic mass of 56. Prior to a supernova, fusion of elements between silicon and iron occurs only in the largest of stars, in the Silicon burning process. A slow neutron capture process, known as the S-process which also occurs during normal stellar nucleosynthesis can create elements up to bismuth with an atomic mass of approximately 209. However, the s-process occurs primarily in low-mass stars that evolve more slowly. Once the core fails to produce enough energy to support the outer envelope of gasses the star explodes as a supernova producing the bulk of elements beyond iron. Production of elements from iron to uranium occurs within seconds in a supernova explosion. Due to the large amounts of energy released, much higher temperatures and densities are reached than at normal stellar temperatures. These conditions allow for an environment where transuranium elements might be formed.