triple alpha process

American  

noun

1. Physics. a nuclear fusion process in which three alpha particles form carbon and release energy.

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triple alpha process Scientific  

/ trĭp′əl /

1. A nuclear fusion reaction in which three helium nuclei (alpha particles) fuse to form a carbon nucleus, thereby releasing energy. Two helium nuclei fuse to form an unstable isotope of beryllium, which under conditions of sufficient temperature and pressure fuses with a third helium nucleus to form carbon before it decays. Triple alpha processes take place in stars in which large quantities of helium have accumulated as the product of proton-proton chain and carbon cycle reactions.

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