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  2. Uranium-238 - Wikipedia

    en.wikipedia.org/wiki/Uranium-238

    The 238 U decay chain contributes six electron anti-neutrinos per 238 U nucleus (one per beta decay), resulting in a large detectable geoneutrino signal when decays occur within the Earth. [3] The decay of 238 U to daughter isotopes is extensively used in radiometric dating , particularly for material older than approximately 1 million years.

  3. Decay chain - Wikipedia

    en.wikipedia.org/wiki/Decay_chain

    The 4n+2 chain of uranium-238 is called the "uranium series" or "radium series". Beginning with naturally occurring uranium-238, this series includes the following elements: astatine, bismuth, lead, mercury, polonium, protactinium, radium, radon, thallium, and thorium. All are present, at least transiently, in any natural uranium-containing ...

  4. Isotopes of uranium - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_uranium

    234 U occurs in natural uranium as an indirect decay product of uranium-238, but makes up only 55 parts per million of the uranium because its half-life of 245,500 years is only about 1/18,000 that of 238 U. The path of production of 234 U is this: 238 U alpha decays to thorium-234. Next, with a short half-life, 234 Th beta decays to ...

  5. Radium-226 - Wikipedia

    en.wikipedia.org/wiki/Radium-226

    The decay-chain of uranium-238, which contains radium-226 as an intermediate decay product. 226 Ra occurs in the decay chain of uranium-238 (238 U), which is the most common naturally occurring isotope of uranium. It undergoes alpha decay to radon-222, which is also radioactive; the decay chain ultimately terminates at lead-206.

  6. Weapons-grade nuclear material - Wikipedia

    en.wikipedia.org/wiki/Weapons-grade_nuclear_material

    Moreover, different isotopes have different critical masses, and the critical mass for many radioactive isotopes is infinite, because the mode of decay of one atom cannot induce similar decay of more than one neighboring atom. For example, the critical mass of uranium-238 is infinite, while the critical masses of uranium-233 and uranium-235 are ...

  7. Radon-222 - Wikipedia

    en.wikipedia.org/wiki/Radon-222

    It is transient in the decay chain of primordial uranium-238 and is the immediate decay product of radium-226. Radon-222 was first observed in 1899, and was identified as an isotope of a new element several years later. In 1957, the name radon, formerly the name of only radon-222, became the name of the element.

  8. Radioactive decay - Wikipedia

    en.wikipedia.org/wiki/Radioactive_decay

    Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha, beta, and gamma decay.

  9. Decay product - Wikipedia

    en.wikipedia.org/wiki/Decay_product

    234m Pa (234 metastable) is the granddaughter of 238 U. These might also be referred to as the daughter products of 238 U. [1] Decay products are important in understanding radioactive decay and the management of radioactive waste. For elements above lead in atomic number, the decay chain typically ends with an isotope of lead or bismuth.