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Supernova nucleosynthesis is the nucleosynthesis of chemical elements in supernova explosions.. In sufficiently massive stars, the nucleosynthesis by fusion of lighter elements into heavier ones occurs during sequential hydrostatic burning processes called helium burning, carbon burning, oxygen burning, and silicon burning, in which the byproducts of one nuclear fuel become, after ...
The model for the formation of this category of supernova is a close binary star system. The larger of the two stars is the first to evolve off the main sequence, and it expands to form a red giant. The two stars now share a common envelope, causing their mutual orbit to shrink.
Artist's conception of a white dwarf, right, accreting hydrogen from the Roche lobe of its larger companion star A nova (pl. novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", Latin for "new") that slowly fades over weeks or months.
Further advances were made, especially to nucleosynthesis by neutron capture of the elements heavier than iron, by Margaret and Geoffrey Burbidge, William Alfred Fowler and Fred Hoyle in their famous 1957 B 2 FH paper, [3] which became one of the most heavily cited papers in astrophysics history.
When two neutron stars collide, a significant amount of neutron-rich matter may be ejected which then quickly forms heavy elements. Cosmic ray spallation is a process wherein cosmic rays impact nuclei and fragment them. It is a significant source of the lighter nuclei, particularly 3 He, 9 Be and 10,11 B, that are not created by stellar ...
Details of the pre-nova moments may help scientists better judge the quality of Type Ia supernovae as standard candles, which is an important link in the argument for dark energy. [46] In July 2019, the Hubble Space Telescope took three images of a Type Ia supernova through a gravitational lens. This supernova appeared at three different times ...
Type II is subdivided into two classes, depending on the shape of the light curve. The light curve for a Type II-L supernova shows a steady ( linear ) decline following the peak brightness. By contrast, the light curve of a Type II-P supernova has a distinctive flat stretch (called a plateau ) during the decline; representing a period where the ...
All elements above 103 are also man-made and are not included. Big Bang nucleosynthesis produced very few nuclei of elements heavier than lithium due to a bottleneck: the absence of a stable nucleus with 8 or 5 nucleons. This deficit of larger atoms also limited the amounts of lithium-7 produced during BBN.