nucleosynthesis: The Carbon-Nitrogen-Oxygen Cycle

The carbon-nitrogen-oxygen cycle requires minute traces of carbon as a catalyst. Four protons are added, one by one, to a carbon nucleus to form a succession of excited (unstable) nuclei of carbon, nitrogen, and oxygen. The intermediate nuclei shed their excess electric charge via beta decay and the final oxygen nucleus spontaneously splits into the original carbon nucleus and a helium-4 nucleus, releasing energy. The net effect is again the combination of four hydrogen nuclei to form one helium-4 nucleus; the carbon is free to begin the cycle over again.

Sections in this article:

• Introduction
• Creation of the Heavier Elements
• The Carbon-Nitrogen-Oxygen Cycle
• The Proton-Proton Cycle
• Transformation of Hydrogen to Helium
• Bibliography

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