An Etymological Dictionary of Astronomy and Astrophysics
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The production of → light elements, roughly three minutes after the → Big Bang when the temperature of the → Universe dropped from 10³² K to approximately 10⁹ K. In a short time interval → protons and → neutrons collided to produce → deuterium. Most of the deuterium then fused with other protons and neutrons to produce → helium and a small amount of → tritium. The element → lithium 7 could also arise form the coalescence of one tritium and two deuterium nuclei. According to the Big Bang nucleosynthesis theory, roughly 25% of the mass of the Universe consists of helium. It also predicts about 0.01% deuterium, and even smaller quantities of lithium. These predictions depend critically on the → baryon-photon ratio. Same as → primordial nucleosynthesis.

→ Big Bang; → nucleosynthesis.

The explosive processes that are believed to occur in supernovae. Explosive carbon burning occurs at a temperature of about 2 × 10⁹ degrees and produces the nuclei from neon to silicon. Explosive oxygen burning occurs near 4 × 10⁹ degrees and produces nuclei between silicon and calcium in atomic weight.At higher temperatures, still heavier nuclei are produced.

→ explosive; → nucleosynthesis.

The process by which → nuclear reactions at very high temperatures and pressures produce the various → chemical elements of the → periodic table, either in the → Big Bang or in stellar interiors. See also → primordial nucleosynthesis, → stellar nucleosynthesis, → explosive nucleosynthesis.

From nucleo-, combining form of → nucleus + → synthesis.

Haste-handâyeš, from hasté→ nucleus + handâyeš→ synthesis.

The formation of → chemical elements in the → early Universe, between about 0.01 seconds and 3 minutes after the → Big Bang, when the nuclei of primordial matter collided and fused with one another. Most of the → helium in the → Universe was created by this process. Same as → Big Bang nucleosynthesis

→ primordial; → nucleosynthesis.

The → nuclear reaction process taking place inside stars, whereby → chemical elements are produced from pre-existing nuclei heavier than → hydrogen and → helium.

→ stellar; → nucleosynthesis.