Cosmogenic isotopes (or cosmogenic nuclides) are rare isotopes created when a high-energy cosmic ray interacts with the nucleus ... Normal licensed releases which occur during the regular operation of a plant or process handling man-made radioactive materials ... are only present due to natural processes, a few isotopes, e.g. tritium (3H), result from both natural processes and human ... There are both radioactive and stable cosmogenic isotopes. Some of these radioisotopes are tritium, carbon-14 and phosphorus-32 ...

See Cosmogenic nuclide for a list of nuclides produced by cosmic ray spallation. The x-process in cosmic rays is the primary ... In formation of a cosmogenic nuclide, a cosmic ray interacts with the nucleus of an in situ solar system atom, causing cosmic ... and thus they are by definition primordial nuclides and not cosmogenic. In contrast, the radioactive nuclide beryllium-7 falls ... on Earth are thought to have been formed by the same process as the cosmogenic nuclides but at an earlier time in cosmic ray ...

... are rare nuclides (isotopes) created when a high-energy cosmic ray interacts with the nucleus of an in situ Solar System atom, ... scientists are able to gain insight into a range of geological and astronomical processes. There are both radioactive and ... Three types of cosmic-ray reactions can occur once a cosmic ray strikes matter which in turn produce the measured cosmogenic ... by the process of cosmic ray spallation on interstellar gas and dust. This explains their higher abundance in cosmic rays as ...

Another minor source of naturally occurring radioactive nuclides are cosmogenic nuclides, that are formed by cosmic ray ... radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by ... Shortly after the discovery of the positron in cosmic ray products, it was realized that the same process that operates in ... Nuclides that are produced by radioactive decay are called radiogenic nuclides, whether they themselves are stable or not. ...

Some of these neutron reactions (such as the r-process and s-process) involve absorption by atomic nuclei of high-temperature ( ... Among the most common are cosmic ray spallation production of neutrons from elements near the surface of the Earth. Alpha ... Some nucleogenic isotopes are stable and others are radioactive. An example of a nucleogenic nuclide is neon-21 produced from ... Neutrons to produce nucleogenic nuclides may be produced by a number of processes, but due to the short half-life of free ...

Chlorine-36 nuclides are also measured to date surface rocks. This isotope may be produced by cosmic ray spallation of calcium ... whereas the radioactive daughter nuclei are not commonly produced by other processes. As oxygen-16 is also common in the ... "Role of in situ cosmogenic nuclides 10Be and 26Al in the study of diverse geomorphic processes". Earth Surface Processes and ... These nuclides are particularly useful to geologists because they are produced when cosmic rays strike oxygen-16 and silicon-28 ...

Alpha nuclide Alpha process (Also known as alpha-capture, or the alpha-ladder) Beta particle Cosmic rays Helion, the nucleus of ... of cosmic rays. The mechanisms of cosmic ray production continue to be debated. The energy of the alpha particle emitted in ... Alpha particles are commonly emitted by all of the larger radioactive nuclei such as uranium, thorium, actinium, and radium, as ... see triple-alpha process and alpha process). In addition, extremely high energy helium nuclei sometimes referred to as alpha ...

Nuclear fission is the opposite process, causing a nucleus to split into two smaller nuclei-usually through radioactive decay. ... or as products of natural energetic processes on Earth, such as cosmic ray bombardment (for example, carbon-14). For 80 of the ... All nuclides with atomic numbers higher than 82 (lead) are known to be radioactive. No nuclide with an atomic number exceeding ... The most common forms of radioactive decay are: Alpha decay: this process is caused when the nucleus emits an alpha particle, ...

Bound within a nucleus, however, both neutrons and protons can decay by the beta decay process. The neutrons and protons in a ... A small natural "neutron background" flux of free neutrons exists on Earth, caused by cosmic ray showers, and by the natural ... Nuclides with the same atomic mass number, but different atomic and neutron numbers, are called isobars. The nucleus of the ... A popular source of the latter type is radioactive antimony-124 plus beryllium, a system with a half-life of 60.9 days, which ...

The nuclides of stable and radioactive elements are also available as a list of nuclides, sorted by length of half-life for ... beryllium and boron are produced mostly through cosmic ray spallation (fragmentation induced by cosmic rays) of carbon, ... produced as individual atoms by nuclear fission of the nuclei of various heavy elements or in other rare nuclear processes. In ... New atoms are also naturally produced on Earth as radiogenic daughter isotopes of ongoing radioactive decay processes such as ...

... the radioactive isotopes of sulfur are all comparatively short-lived. 35S is formed from cosmic ray spallation of 40Ar in the ... Zhu, Long (2019-12-01). "Possibilities of producing superheavy nuclei in multinucleon transfer reactions based on radioactive ... Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). ... in the so-called alpha process of exploding type II supernovas (see silicon burning). Other than 35S, ...

The ground state of this particular nucleus, tantalum-180, is radioactive with a comparatively short half-life of 8 hours; in ... such as decay products or cosmic ray spallation. Many naturally occurring radioisotopes (another 53 or so, for a total of about ... as daughter products of decay processes of primordial nuclides (for example, radium from uranium) or from ongoing energetic ... Stable nuclides are nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive ...

Cosmic ray spallation is a process wherein cosmic rays impact nuclei and fragment them. It is a significant source of the ... Naturally occurring nuclear reactions powered by radioactive decay give rise to so-called nucleogenic nuclides. This process ... Cosmic ray spallation process reduces the atomic weight of interstellar matter by the impact with cosmic rays, to produce some ... reacts with a nucleus of another atom to change the nucleus into another nuclide. This process may also cause the production of ...

Save for the first five elements, which were produced in the Big Bang and other cosmic ray processes, stellar nucleosynthesis ... and by the radioactive decay of radioactive primordial nuclides left over from the initial formation of the solar system (such ... Nuclear transmutation occurs in any process where the number of protons or neutrons in the nucleus of an atom is changed. A ... Nuclides with mass number greater than 64 are predominantly produced by neutron capture processes-the s-process and r-process- ...

He inferred that this was a decay product of radioactive iodine-129. This isotope is produced slowly by cosmic ray spallation ... although the process is different from pumping a laser). Because a 129Xe nucleus has a spin of 1/2, and therefore a zero ... less xenon is destroyed than is produced from the beta decay of its parent nuclides. This phenomenon called xenon poisoning can ... Instead, xenon is formed during supernova explosions during the r-process, by the slow neutron-capture process (s-process) in ...

The production of 26Al by cosmic ray interactions in unshielded materials is used as a monitor of the time of exposure to ... The isotope is mainly produced in supernovas ejecting many radioactive nuclides in the interstellar medium. The isotope is ... Other extinct radioactive nuclei, which clearly had a stellar origin, were then being discovered. That 26Al was present in the ... ratios are coupled to different chemical phases in a sample and are the result of normal chemical separation processes ...

Post-primordial isotopes were created by cosmic ray bombardment as cosmogenic nuclides (e.g., tritium, carbon-14), or by the ... the nucleogenic nuclides, and any radiogenic nuclides formed by ongoing decay of a primordial radioactive nuclide, such as ... A nuclide is a species of an atom with a specific number of protons and neutrons in the nucleus, for example, carbon-13 with 6 ... see triple alpha process). 53 stable nuclides have an even number of protons and an odd number of neutrons. They are a minority ...

During the 1970s, cosmic ray spallation was proposed as a source of deuterium. That theory failed to account for the abundance ... The problem here again is that deuterium is very unlikely due to nuclear processes, and that collisions between atomic nuclei ... In addition to these stable nuclei, two unstable or radioactive isotopes were produced: the heavy hydrogen isotope tritium (3H ... Lithium-7 and lithium-6 produced in the Big Bang are on the order of: lithium-7 to be 10−9 of all primordial nuclides; and ...

... cosmic ray induced) processes that produce them in nature freshly. A few others are naturally produced by nucleogenic processes ... A radiogenic nuclide is a nuclide that is produced by a process of radioactive decay. It may itself be radioactive (a ... Most of the radiogenic heating in the Earth results from the decay of the daughter nuclei in the decay chains of uranium-238 ... a radiogenic nuclide is often not radioactive. In this case, if its precursor nuclide has a half-life too short to have ...

Cosmic ray dating is only useful on material that has not been melted, since melting erases the crystalline structure of the ... His calculations did not account for heat produced via radioactive decay (a then unknown process) or, more significantly, ... Because of this segregation in the parent and daughter nuclides during the formation of the meteorite, this allowed a much more ... isotopes would be shown to have nuclei with differing numbers of the neutral particles known as "neutrons". In that same year, ...

Cosmic ray neutrino experiments detect neutrinos from space to study both the nature of neutrinos and the cosmic sources ... Neutrinos can interact with a nucleus, changing it to another nucleus. This process is used in radiochemical neutrino detectors ... Neutrinos are created by various radioactive decays; the following list is not exhaustive, but includes some of those processes ... the resultant neutron-rich daughter nuclides rapidly undergo additional beta decays, each converting one neutron to a proton ...

... is a product of cosmic ray spallation on various isotopes of xenon in the atmosphere, in cosmic ray muon interaction with ... unless the nuclide is incorporated into a medication that accumulates in the nucleus, or into DNA (this is never the case is ... to reduce the uptake of radioactive iodine compounds by the thyroid before the highly radioactive isotopes have had time to ... The process of buildup of xenon-135 from accumulated iodine-135 can temporarily preclude a shut-down reactor from restarting. ...

... or as a result of neutrons from radioactive decay or reactions with cosmic ray particles. The microscopic tracks left by these ... Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons, the ... This process is the source of so-called delayed neutrons, which play an important role in control of a nuclear reactor. The ... Chart of the Nuclides, twelfth edition. Knolls Atomic Power Laboratory, General Electric Company. "Introduction to ANL's IFR ...

Alternative energy Cosmic ray spallation Spallation Neutron Source ISIS neutron source Hybrid nuclear fusion Notes "IThec , Un ... The long-lived transuranic elements in nuclear waste can in principle be fissioned, releasing energy in the process and leaving ... The other uses neutrons created through spallation of heavy nuclei by charged particles such as protons accelerated by a ... While they can be transmuted into fissile material with thermal neutrons, some nuclides need as many as three successive ...

... cosmic ray spallation of nuclei, and light elements absorbing alpha particles and emitting a neutron. The half-life of 239Np is ... A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium ... Recovering uranium and plutonium from spent nuclear fuel for reuse is one of the major processes of the nuclear fuel cycle. As ... They confirmed that this isotope was also a beta emitter and must hence decay to the unknown nuclide 23793. They attempted to ...

Clayton had previously attempted to establish gamma-ray-line astronomy from r process radioactive nuclei; but r-process nuclei ... each phase of interstellar gas contains a distinctly different concentration of each of the extinct radioactive nuclides, ... He named these solids stardust, postulating thereby a new component of interstellar Cosmic dust. Stardust inherits its unusual ... ray-emitting nuclei as nucleosynthesis sources for the field of gamma-ray astronomy of line transitions from radioactive nuclei ...

Such excess energy is emitted through any of several processes of radioactive decay, resulting in a stable nuclide or sometimes ... nucleus nuclide An atomic species characterized by the specific composition of its nucleus, i.e. by its number of protons, its ... The ray can be formed by any wave: optical, acoustic, microwave, X-ray, etc. angle of reflection The change in direction of a ... Coulomb's law converging lens cosmic background radiation creep crest The point on a wave with the maximum value or upward ...

... which are transformed to another nuclide, frequently a radionuclide. This process accounts for much of the radioactive material ... Care must be taken to avoid using materials whose nuclei undergo fission or neutron capture that causes radioactive decay of ... or from other nuclear reactions such as radioactive decay or particle interactions with cosmic rays or within particle ... In materials of low atomic number such as hydrogen, a low energy gamma ray may be more penetrating than a high energy neutron. ...

In 1938, during a nuclear experiment conducted at Ohio State University, a few radioactive nuclides were produced that ... or by cosmic ray spallation of 146Nd. Both isotopes of natural europium have larger mass excesses than sums of those of their ... Its partial half-life for alpha decay is about 6.3×109 years, and the relative probability for a 145Pm nucleus to decay in this ... In 1963, ion-exchange methods were used at ORNL to prepare about ten grams of promethium from nuclear reactor fuel processing ...

Such radioactive nuclei can exhibit half-lives ranging from small fractions of a second to many years. Neutron activation is ... together with its dominant natural production pathway from cosmic ray-air interactions and historical production from ... Neutron activation is the process in which neutron radiation induces radioactivity in materials, and occurs when atomic nuclei ... Salted bomb Table of nuclides Manual for reactor produced radioisotopes from the International Atomic Energy Agency Neeb, Karl ...