nucleosynthesis

American  

[noo-klee-oh-sin-thuh-sis, nyoo-] / ˌnu kli oʊˈsɪn θə sɪs, ˌnyu- /

noun

Physics, Astronomy.

1. the formation of new atomic nuclei by nuclear reactions, thought to occur in the interiors of stars and in the early stages of development of the universe.

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nucleosynthesis British  

/ ˌnjuːklɪəʊˈsɪnθɪsɪs /

noun

1. astronomy the formation of heavier elements from lighter elements by nuclear fusion in stars

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nucleosynthesis Scientific  

/ no̅o̅′klē-ō-sĭn′thĭ-sĭs /

1. The process by which heavier chemical elements are synthesized in the interiors of stars from hydrogen nuclei and other previously synthesized elements. Precisely which elements are involved in nucleosynthesis depends on the age and mass of the star. The most prevalent reaction in smaller stars like our Sun is the fusion of hydrogen into helium by the proton-proton chain; in more massive stars this fusion occurs via the carbon cycle. When a star is burning hydrogen in its core, it is a main-sequence star. In older stars such as the red giants, nucleosynthesis involves the burning of heavier elements created by earlier fusion; for example, helium may burn via the triple alpha process. More massive stars—over eight solar masses—also fuse carbon into neon and magnesium, oxygen into silicon and sulfur, and silicon into iron. The nucleosynthesis of iron is the precursor to the transition into the supernova phase.

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Other Word Forms

• nucleosynthetic adjective

Etymology

Origin of nucleosynthesis

First recorded in 1955–60; nucleo- + synthesis

Example Sentences

He said the key to charting the known universe’s path through time is in untangling a complex process known as stellar nucleosynthesis, and then deciphering the subatomic-level reactions inside that process.

From Salon • Jan. 26, 2024

Thus, it is an indicator of the nucleosynthesis of heavy elements.

From Science Daily • Nov. 2, 2023

Helium’s origins go back to just a few minutes after the big bang, when hydrogen, helium and a bit of lithium were produced during what is called big bang nucleosynthesis.

From Scientific American • Jul. 4, 2023

The 12C + 12C reaction and the impact on nucleosynthesis in massive stars.

From Nature • May 22, 2018

Hoyle also realized that if stars imploded they would liberate huge amounts of heat–100 million degrees or more, enough to begin to generate the heavier elements in a process known as nucleosynthesis.

From "A Short History of Nearly Everything" by Bill Bryson