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This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.
This element also has 18 meta states, with the most stable being 177m Lu (t 1/2 160.4 days), 174m Lu (t 1/2 142 days) and 178m Lu (t 1/2 23.1 minutes). The known isotopes of lutetium range in mass number from 149 to 190. The primary decay mode before the most abundant stable isotope, 175 Lu, is electron capture (with some alpha and positron ...
Half-life (symbol t½) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive. The term is also used more generally to characterize any type of exponential (or, rarely ...
Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 is also used for that purpose. Plutonium-239 is also one of the three main isotopes demonstrated usable as fuel in thermal spectrum nuclear reactors, along with uranium-235 and uranium-233. Plutonium-239 has a half-life of 24,110 years.
242 Pu's half-life is about 15 times as long as 239 Pu's half-life; therefore, it is 1/15 as radioactive and not one of the larger contributors to nuclear waste radioactivity. 242 Pu's gamma ray emissions are also weaker than those of the other isotopes. [14] 243 Pu has a half-life of only 5 hours, beta decaying to americium-243.
Naturally occurring lithium (3 Li) is composed of two stable isotopes, lithium-6 (6 Li) and lithium-7 (7 Li), with the latter being far more abundant on Earth. Both of the natural isotopes have an unexpectedly low nuclear binding energy per nucleon (5 332.3312(3) keV for 6 Li and 5 606.4401(6) keV for 7 Li) when compared with the adjacent lighter and heavier elements, helium (7 073.9156(4) keV ...
34 S abundances vary greatly (between 3.96 and 4.77 percent) in natural samples. Sulfur (16 S) has 23 known isotopes with mass numbers ranging from 27 to 49, four of which are stable: 32 S (95.02%), 33 S (0.75%), 34 S (4.21%), and 36 S (0.02%). The preponderance of sulfur-32 is explained by its production from carbon-12 plus successive fusion ...
Xenon-124 is an isotope of xenon that undergoes double electron capture to tellurium -124 with a very long half-life of 1.8 × 1022 years, more than 12 orders of magnitude longer than the age of the universe ((13.799 ± 0.021) × 109 years). Such decays have been observed in the XENON1T detector in 2019, and are the rarest processes ever ...