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A version of the periodic table indicating the origins – including big bang nucleosynthesis – of the elements. 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 ...
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons (protons and neutrons) and nuclei. According to current theories, the first nuclei were formed a few minutes after the Big Bang, through nuclear reactions in a process called Big Bang nucleosynthesis. [1]
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.
Big Bang nucleosynthesis produced both lithium-7 and beryllium-7, and indeed the latter dominates the primordial synthesis of mass 7 nuclides. On the other hand, the Big Bang produced lithium-6 at levels more than 1000 times smaller. 7 4 Be later decayed via electron capture (half-life 53.22 days) into 7 3 Li
While the original theory neglected a number of processes important to the formation of heavy elements, subsequent developments showed that Big Bang nucleosynthesis is consistent with the observed constraints on all primordial elements. Formally titled "The Origin of Chemical Elements", it was published in the April 1948 issue of Physical ...
This process (cosmogenic nucleosynthesis) was discovered somewhat by accident during the 1970s: models of Big Bang nucleosynthesis suggested that the amount of deuterium was too large to be consistent with the expansion rate of the universe and there was therefore great interest in processes that could generate deuterium after the Big Bang ...
The current consensus on the origins of elements and isotopes are that only hydrogen and helium (and traces of lithium) can be formed in a homogeneous Big Bang (see Big Bang nucleosynthesis), while all other elements and their isotopes are formed in cosmic objects that formed later, such as in stars and their explosions. [11]
However, very soon thereafter, at twenty minutes after the Big Bang, the Universe became too cool for any further nuclear fusion or nucleosynthesis. At this point, the elemental abundances were nearly fixed, with the only change as some of the radioactive products of Big Bang nucleosynthesis (such as tritium ) decay. [ 11 ]