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In contrast, the radioactive nuclide beryllium-7 falls into the same light element range but has a half-life too short for it to have been formed before the formation of the Solar System, so that it cannot be a primordial nuclide. Since the cosmic ray spallation route is the most likely source of beryllium-7 in the environment, that isotope is ...
A similar radiogenic series is derived from the long-lived radioactive primordial nuclide 232 Th. These nuclides are described as geogenic, meaning that they are decay or fission products of uranium or other actinides in subsurface rocks. [6] All such nuclides have shorter half-lives than their parent radioactive primordial nuclides.
It is prevented from having a stable isotope with 4 protons and 6 neutrons by the very large mismatch in proton/neutron ratio for such a light element. (Nevertheless, beryllium-10 has a half-life of 1.36 million years, which is too short to be primordial, but still indicates unusual stability for a light isotope with such an imbalance.)
Certain light (low atomic number) primordial nuclides (isotopes of lithium, beryllium and boron) are thought to have been created not only during the Big Bang, but also (and perhaps primarily) to have been made after the Big Bang, but before the condensation of the Solar System, by the process of cosmic ray spallation on interstellar gas and ...
One of the primordial nuclides is tantalum-180m, which is predicted to have a half-life in excess of 10 15 years, but has never been observed to decay. The even-longer half-life of 2.2 × 10 24 years of tellurium-128 was measured by a unique method of detecting its radiogenic daughter xenon-128 and is the longest known experimentally measured ...
Two beta-decay stable nuclides exist for odd neutron numbers 1 (2 H and 3 He), 3 (5 He and 6 Li – the former having an extremely short half-life), 5 (9 Be and 10 B), 7 (13 C and 14 N), 55 (97 Mo and 99 Ru), and 85 (145 Nd and 147 Sm); the first four cases involve very light nuclides where odd-odd nuclides are more stable than their ...
The radiant point of the shower is a right angle between the Big Dipper and the bright star Arcturus, according to EarthSky. But the meteors will be visible in all parts of the sky, so it’s not ...
At least 3,300 nuclides have been experimentally characterized [1] (see List of radioactive nuclides by half-life for the nuclides with decay half-lives less than one hour). A nuclide is defined conventionally as an experimentally examined bound collection of protons and neutrons that either is stable or has an observed decay mode .