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An example of a nucleogenic nuclide is neon-21 produced from neon-20 that absorbs a thermal neutron (though some neon-21 is also primordial). [1] Other nucleogenic reactions that produce heavy neon isotopes are (fast neutron capture, alpha emission) reactions, starting with magnesium-24 and magnesium-25, respectively. [2]
For example, some stable isotopes such as neon-21 and neon-22 are produced by several routes of nucleogenic synthesis, and thus only part of their abundance is primordial. Nuclear reactions due to cosmic rays. By convention, these reaction-products are not termed "nucleogenic" nuclides, but rather cosmogenic nuclides. Cosmic rays continue to ...
Neon has three stable isotopes: 20 Ne (90.48%), 21 Ne (0.27%) and 22 Ne (9.25%). [13] 21 Ne and 22 Ne are partly primordial and partly nucleogenic (i.e. made by nuclear reactions of other nuclides with neutrons or other particles in the environment) and their variations in natural abundance are well understood.
Reactions with neutrons are important in nuclear reactors and nuclear weapons. While the best-known neutron reactions are neutron scattering, neutron capture, and nuclear fission, for some light nuclei (especially odd-odd nuclei) the most probable reaction with a thermal neutron is a transfer reaction:
Other nuclides may be occasionally produced naturally by rare cosmogenic interactions or as a result of other natural nuclear reactions (nucleogenic nuclides), but are difficult to detect. Further shorter-lived nuclides have been detected in the spectra of stars, such as isotopes of technetium, promethium, and some actinides.
Neon has three main stable isotopes: 20 Ne, 21 Ne and 22 Ne, with 20 Ne produced by cosmic nucleogenic reactions, causing high abundance in the atmosphere. [97] [103] 21 Ne and 22 Ne are produced in the earth's crust as a result of interactions between alpha and neutron particles with light elements; 18 O, 19 F and 24,25 Mg. [104]
Other types of natural nuclear reactions produce nuclides that are said to be nucleogenic nuclides. An example of nuclides made by nuclear reactions, are cosmogenic 14 C (radiocarbon) that is made by cosmic ray bombardment of other elements, and nucleogenic 239 Pu which is still being created by neutron bombardment of natural 238 U
The neon-burning process is a set of nuclear fusion reactions that take place in evolved massive stars with at least 8 Solar masses. Neon burning requires high temperatures and densities (around 1.2×10 9 K or 100 keV and 4×10 9 kg/m 3 ).