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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 ...
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 ...
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 ...
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 ...
Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus. [5] They are generally produced in the process of alpha decay but may also be produced in other ways. Alpha particles are named after the first letter in the Greek alphabet, α.
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).}
Nuclear physics. 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 ...
Schematic of energy levels involved in two photons absorption. In atomic physics, two-photon absorption (TPA or 2PA), also called two-photon excitation or non-linear absorption, is the simultaneous absorption of two photons of identical or different frequencies in order to excite an atom or a molecule from one state (usually the ground state), via a virtual energy level, to a higher energy ...