Oxygen burning process

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Nuclear processes

Radioactive decay processes Alpha decay Beta decay Cluster decay Double beta decay Double electron capture Electron capture Gamma radiation Internal conversion Isomeric transition Neutron emission Positron emission Proton emission Spontaneous fission Nucleosynthesis Nuclear fusion Proton-proton chain reaction CNO cycle Triple-alpha process Carbon burning process Neon burning process Oxygen burning process Silicon burning process Neutron capture The R-process The S-process Proton capture: The P-process The Rp-process Spallation

The oxygen burning process is a nuclear fusion reaction that occurs in massive stars that have used up the lighter elements in their cores. It occurs at 1.5×10⁹ K and densities of 10¹⁰ kg/m³.

16O + 16O	→	32S + γ
	→	31S + n
	→	31P + 1H
	→	28Si + 4He
	→	24Mg + 24He

With the neon burning process an inert core of O-Mg forms in the centre of the star. As the neon burning turns off, the core contracts and heats up to the ignition point for the oxygen burning. In about six months to one year the star consumes its oxygen, accumulating a new core rich in silicon. This core is inert because it is not hot enough. Once oxygen is exhausted, the core cools and contracts. This contraction heats it up to the point that silicon burning process ignites. Proceeding outward, there are an oxygen burning shell, followed by the neon shell, the carbon shell, the helium shell and the hydrogen shell.