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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 heavy elements are produced by: nuclear fusion for nuclei up to 34 S; silicon photodisintegration rearrangement and quasiequilibrium during silicon burning for nuclei between 36 Ar and 56 Ni; and rapid capture of neutrons during the supernova's collapse for elements heavier than iron.
A kilonova was also thought to have caused the long gamma-ray burst GRB 211211A, discovered in December 2021 by Swift’s Burst Alert Telescope (BAT) and the Fermi Gamma-ray Burst Monitor (GBM). [ 25 ] [ 26 ] These discoveries challenge the formerly prevailing theory that long GRBs exclusively come from supernovae , the end-of-life explosions ...
Neutron star mergers are a recently discovered major source of elements produced in the r-process. 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.
Heavier elements than iron are formed during this explosion by neutron capture, and from the pressure of the neutrinos pressing into the boundary of the "neutrinosphere", seeding the surrounding space with a cloud of gas and dust which is richer in heavy elements than the material from which the star originally formed. [23]
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.
In the case of a nova, the infalling matter causes a hydrogen fusion surface explosion that does not disrupt the star. [ 13 ] Type Ia supernovae differ from Type II supernovae , which are caused by the cataclysmic explosion of the outer layers of a massive star as its core collapses, powered by release of gravitational potential energy via ...