Search results
Results from the WOW.Com Content Network
In astrophysics, stellar nucleosynthesis is the creation of chemical elements by nuclear fusion reactions within stars. Stellar nucleosynthesis has occurred since the original creation of hydrogen, helium and lithium during the Big Bang. As a predictive theory, it yields accurate estimates of the observed abundances of the elements.
The products of stellar nucleosynthesis are generally dispersed into the interstellar gas through mass loss episodes and the stellar winds of low mass stars. The mass loss events can be witnessed today in the planetary nebulae phase of low-mass star evolution, and the explosive ending of stars, called supernovae , of those with more than eight ...
Eleanor Margaret Burbidge, FRS (née Peachey; 12 August 1919 – 5 April 2020) was a British-American observational astronomer and astrophysicist.In the 1950s, she was one of the founders of stellar nucleosynthesis and was first author of the influential B 2 FH paper.
Natural transmutation by stellar nucleosynthesis in the past created most of the heavier chemical elements in the known existing universe, and continues to take place to this day, creating the vast majority of the most common elements in the universe, including helium, oxygen and carbon.
While the total number of "catalytic" nuclei are conserved in the cycle, in stellar evolution the relative proportions of the nuclei are altered. When the cycle is run to equilibrium, the ratio of the carbon-12/carbon-13 nuclei is driven to 3.5, and nitrogen-14 becomes the most numerous nucleus, regardless of initial composition.
The B 2 FH paper was ostensibly a review article summarising recent advances in the theory of stellar nucleosynthesis. [8] However, it went beyond simply reviewing Hoyle's work, by incorporating observational measurements of elemental abundances published by the Burbidges, and Fowler's laboratory experiments on nuclear reactions.
Nucleogenesis (also known as nucleosynthesis) as a general phenomenon is a process usually associated with production of nuclides in the Big Bang or in stars, by nuclear reactions there. Some of these neutron reactions (such as the r-process and s-process ) involve absorption by atomic nuclei of high-temperature (high energy) neutrons from the ...
He also formed a group at Cambridge exploring stellar nucleosynthesis in ordinary stars and was bothered by the paucity of stellar carbon production in existing models. He noticed that one existing process would be made a billion times more productive if the carbon-12 nucleus had a resonance at 7.7 MeV, but nuclear physicists at the time ...