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  2. Polonium-210 - Wikipedia

    en.wikipedia.org/wiki/Polonium-210

    Polonium-210. Polonium-210 (210 Po, Po-210, historically radium F) is an isotope of polonium. It undergoes alpha decay to stable 206 Pb with a half-life of 138.376 days (about 4⁄ months), the longest half-life of all naturally occurring polonium isotopes (210–218 Po). [1] First identified in 1898, and also marking the discovery of the ...

  3. Alpha decay - Wikipedia

    en.wikipedia.org/wiki/Alpha_decay

    Nuclear physics. Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or "decays" into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two. An alpha particle is identical to the nucleus of a ...

  4. Alpha-particle spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Alpha-particle_spectroscopy

    Alpha spectrometry (also known as alpha (-particle) spectroscopy) is the quantitative study of the energy of alpha particles emitted by a radioactive nuclide that is an alpha emitter. As emitted alpha particles are mono-energetic (i.e. not emitted with a spectrum of energies, such as beta decay) with energies often distinct to the decay they ...

  5. Polonium - Wikipedia

    en.wikipedia.org/wiki/Polonium

    Polonium is a radioactive element that exists in two metallic allotropes. The alpha form is the only known example of a simple cubic crystal structure in a single atom basis at STP (space group Pm 3 m, no. 221). The unit cell has an edge length of 335.2 picometers; the beta form is rhombohedral. [9][10][11] The structure of polonium has been ...

  6. Alpha particle - Wikipedia

    en.wikipedia.org/wiki/Alpha_particle

    Alpha particles have a net spin of zero. When produced in standard alpha radioactive decay, alpha particles generally have a kinetic energy of about 5 MeV and a velocity in the vicinity of 4% of the speed of light. They are a highly ionizing form of particle radiation, with low penetration depth (stopped by a few centimetres of air, or by the ...

  7. Isotopes of polonium - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_polonium

    Isotopes of polonium (84Po) There are 42 isotopes of polonium (84 Po). They range in size from 186 to 227 nucleons. They are all radioactive. 210 Po with a half-life of 138.376 days has the longest half-life of any naturally-occurring isotope of polonium and is the most common isotope of polonium. It is also the most easily synthesized polonium ...

  8. Decay heat - Wikipedia

    en.wikipedia.org/wiki/Decay_heat

    Decay heat. RTG pellet glowing red due to the heat generated by the radioactive decay of plutonium-238 dioxide, after a thermal isolation test. Decay heat is the heat released as a result of radioactive decay. This heat is produced as an effect of radiation on materials: the energy of the alpha, beta or gamma radiation is converted into the ...

  9. Decay energy - Wikipedia

    en.wikipedia.org/wiki/Decay_energy

    alpha decay. The decay energy is the mass difference Δm between the parent and the daughter atom and particles. It is equal to the energy of radiation E. If A is the radioactive activity, i.e. the number of transforming atoms per time, M the molar mass, then the radiation power P is: m {\displaystyle P=\Delta {m}\left ( {\frac {A} {M}}\right).}