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The intermediates in the thorium-232 decay chain are all relatively short-lived; the longest-lived intermediate decay products are radium-228 and thorium-228, with half lives of 5.75 years and 1.91 years, respectively. All other intermediate decay products have half lives of less than four days. [5] The following table lists the intermediate ...
One isotope, 229 Th, has a nuclear isomer (or metastable state) with a remarkably low excitation energy, [5] recently measured to be 8.355 733 554 021 (8) eV [6] [7] It has been proposed to perform laser spectroscopy of the 229 Th nucleus and use the low-energy transition for the development of a nuclear clock of extremely high accuracy.
A further 10 nuclides, platinum-190, samarium-147, lanthanum-138, rubidium-87, rhenium-187, lutetium-176, thorium-232, uranium-238, potassium-40, and uranium-235 have half-lives between 7.0 × 10 8 and 4.83 × 10 11 years, which means they have experienced at least 0.5% depletion since the formation of the Solar System about 4.6 × 10 9 years ...
Uranium-232 (232 U) is an isotope of uranium.It has a half-life of around 69 years and is a side product in the thorium cycle.It has been cited as an obstacle to nuclear proliferation using 233 U as the fissile material, because the intense gamma radiation emitted by 208 Tl (a daughter of 232 U, produced relatively quickly) makes the 233 U contaminated with it more difficult to handle.
Most of the time (92%), it undergoes beta plus decay to 230 Th, with a minor (8%) beta-minus decay branch leading to 230 U. It also has a very rare (.003%) alpha decay mode leading to 226 Ac. [10] It is not found in nature because its half-life is short and it is not found in the decay chains of 235 U, 238 U, or 232 Th. It has a mass of 230. ...
has a relatively short half-life (68.9 years), and some decay products emit high energy gamma radiation, such as 220 Rn, 212 Bi and particularly 208 Tl. The full decay chain, along with half-lives and relevant gamma energies, is: The 4n decay chain of 232 Th, commonly called the "thorium series" 232 U decays to 228 Th where it joins the decay ...
Considering all decay modes, various models indicate a shift of the center of the island (i.e., the longest-living nuclide) from 298 Fl to a lower atomic number, and competition between alpha decay and spontaneous fission in these nuclides; [83] these include 100-year half-lives for 291 Cn and 293 Cn, [55] [78] a 1000-year half-life for 296 Cn ...
A comprehensive table to decay chains would list them all. If you're asking how any radioactive isotopes came to be radioactive in the first place, that's a separate question. :-) Samw 04:03, 29 Dec 2004 (UTC) Congruence of integers is defined in Modular arithmetic. An alpha decay reduces the nucleon count by 4, and a beta decay leaves it ...